Monday, August 29, 2011

8th Grade Unit #1 Mechanics HONORS


8th Grade Unit#1 -Mechanics  HONORS


8th Grade Unit#1 -Mechanics
motion
                        




VSC CONTENT INDICATORS AND OBJECTIVES
The shaded concepts are tested on the MSA and should be the focus of this unit.

5.8.A. Mechanics
1.  Develop an explanation of motion using the relationships among time, distance, velocity, and acceleration.
a. Observe, describe, and compare the motions of objects using position,
speed, velocity, and the direction.
b. Based on data given or collected, graph and calculate average speed using distance and time.
c. Compare accelerated and constant motions using time, distance, and velocity.
dDescribe and calculate acceleration using change in the speed and time.
2. Identify and relate formal ideas (Newton’s Laws) about the interaction of force and motion to real world experiences.
a. Investigate and explain the interaction of force and motion that causes objects that are at rest to move.
bDemonstrate and explain, through a variety of examples, that moving objects will stay in motion at the same speed and in the same direction unless acted on by an unbalanced force.
c. Investigate and collect data from multiple trials, about the motion that explain the motion that results when the same force acts on objects of different mass; and when different amounts of force  act on objects of the same mass.
d. Based on data collected and organized, explain qualitatively the relationship between net force applied to an object and its mass for a given acceleration.
e. Calculate the net force given the mass and acceleration.
3.  Recognize and explain that every object exerts gravitational force on every other object.
a. Explain the difference between mass and weight.
·   Mass is a measure of inertia
·   Weight is a measure of the force of gravity
b. Describe the relationship between the gravitational force and the masses of the attracting objects.
c. Describe the relationship between the gravitational force and the distance between the attracting objects.
d. Recognize and cite examples showing that mass remains the same in all locations while weight may vary with a change in location (weight on Earth compared to weight on moon).
e.    Recognize that gravity is the force that holds planets, moons, and satellites in their orbits.
4.  Recognize and explain that energy can neither be created nor destroyed; rather it changes form or is transferred through the action of forces.
a. Observe and describe the relationship between the distance an object is moved by a force and the change in its potential energy or kinetic energy, such as in a slingshot, in mechanical toys, the position of an object and its potential energy..
b. Identify the relationship between the amount of energy transferred (work) to the product of the applied force and the distance moved in the direction of that force.
c. Identify and describe that simple   machines (levers and inclined planes) may reduce the amount of effort required to do work.
·  Calculate input and output work using force and distance
·  Demonstrate that input work is always greater than output work

VSC SKILLS AND PROCESSES INDICATORS
1.6-8.A Constructing Knowledge
1. Design, analyze or carry out simple investigations and formulate appropriate conclusions based on the data obtained or provided.
1.6-8.B. Applying Evidence and Reasoning
1. Review data from a simple experiment, summarize the data, and construct a logical argument about the cause-and-effect relationships in the experiment.
1.6-8.C Communicating Scientific Information
1. Develop explanations that explicitly link data from investigations conducted, selected readings and when appropriate, contributions from historical discoveries.
1.6-8.D Making Models
  1. Analyze the value and the limitations of different types of models in explaining real things and processes.



CONCEPTUAL UNDERSTANDING
· The motion of an object is determined by its change of position relative to a reference point.
· Displacement refers to the overall change in position of an object.
· Speed describes how fast an object is moving.
· Velocity is speed plus direction.
· The velocity of an object changes when either/both the speed or direction of motion changes.
· An object moving in a circle at constant speed is accelerating because the direction of motion is continuously changing.
· Acceleration is the rate at which velocity changes.
· Acceleration involves increasing speed, decreasing speed, or changing direction.
· Motion of an object falling freely is an example of constant acceleration-motion.
· In the absence of air resistance, all objects regardless of mass fall with the same acceleration.
· When the net force or unbalanced force acting on an object is zero, the object either remains at rest or moves with constant velocity. Otherwise, the object accelerates.
· Inertia is the property of an object that enables it to resist change in state of motion.
· The net force or unbalanced force acting on an object is directly proportional and always in the same direction as the acceleration of the body.
· For a given acceleration, the net force varies proportionally with mass. The greater the mass, the more force is needed to produce a given acceleration.
· For a given net force, the acceleration varies inversely with mass. The greater the mass, the smaller the acceleration produced for a given net force exerted.
· For every action there is an equal and opposite reaction.
· Energy is the ability to do work.
· Energy can neither be created nor destroyed but can only be converted from one form into another.
· Kinetic energy is the energy an object has because of its motion. The greater the speed, the greater is the kinetic energy.
· Potential energy is the energy of an object due to its position. The greater the height to which an object is raised or the more a spring is stretched/ compressed, the greater is its potential energy.






PRETEST-Copy these questions into your journal and answer them there (as best as you can)

 Under what circumstances is an object accelerating?
· If an object is moving with constant speed, does it necessarily move with constant velocity?
· What is the acceleration of an object if it is moving with constant velocity of 400 m/s?
· What is the acceleration of an object thrown up in the air when it reaches its highest point?
· What happens to the acceleration of an object thrown straight up while it is rising?
· Under what circumstances is the net force acting on an object equal to zero?
· What is the net force acting on an object that is moving in a circle at constant speed?
· How does the acceleration of an object change with the net force acting on it?
· Why do you lurch forward in a bus that suddenly slows? Why do you lurch backward when it picks up speed?
· A force of gravity pulls downward on a book on a table. What force prevents the book from accelerating downward?
· Why does the action-reaction pair of forces in Newton’s Third Law not cancel?
· How does the force exerted by the Sun on the Earth as the Earth moves around the Sun compare to the force that the Earth exerts on the Sun?
· What property of an object refers to its resistance to change in state of motion?
· How does friction affect the net force on an object?
· How great is the force of friction compared with your push on a crate that doesn’t move on a level floor?
· If the mass of a sliding object is tripled while a constant net force is applied, by how much does the acceleration change?
· If the speed of a moving object is doubled, by how much does its kinetic energy change?
· What happens to the kinetic energy of an object that is thrown straight up in the air while the object is rising? Where does the kinetic energy go?
· An object is dropped from a certain height above the ground. In the absence of air resistance, how does the kinetic energy of the object just before it hits the ground compare with its potential energy when it was released?
· Describe the energy transformation of a swinging pendulum.




FIRST BIG ASSIGNMENT - Please look up these words in dictionaries and encyclopedias and put the words and their definitions in your journal.

VOCABULARY

Distance
Displacement
Speed
Acceleration
Mass
Inertia
Force
Net force
Equilibrium
Gravity
Friction
Newton’s First Law
Newton’s Second Law
Newton’s Third Law
Action-reaction forces
Energy
Kinetic energy
Potential energy
Conservation of energy






Assignment=Please double click this web site and scroll down to "Kinetic Energy" and click there

Then watch the power point and take 20 notes from the movie in your journal

Finally click the quiz, copy each question in your journal and take it there

































Please copy these questions into your journal and answer them there

Date ___________________
Complete each sentence using the words in the word list.


Acceleration
Friction
Inertia
Energy

Equilibrium
Distance
Gravity
Speed


_______________
1.  
    The ____ shown on the map is out of proportion.
_______________
2.  
   His quick ____ helped him win the moto cross race.
_______________
3.  
  Some planets do not have ____.
_______________
4.  
   Use the highway map, Matthew, to find the ____ from New York City to Los Angeles.
_______________
5.  
  When she rubbed her hands together the ____ made them warmer.
_______________
6.  
   Although my grandmother's house is a considerable ____ from town, she walks to the post office there every day.
_______________
7.  
__  __ has to do with rest and motion.
_______________
8.  
  After the hard blow to his head, Nick found he lost his sense of ____.
_______________
9.  
   The gasoline is an example of chemical potential ____.
_______________
10.  
___  _ and agility gave an advantage to Coelophysis when facing a hungry armored phytosaur.
_______________
11.  
  My brother's state of ____ is changed only when my mother calls him for a meal.
_______________
12.  
  Jonas felt the crescendo of ____ as he slide down the hill on the sled.
_______________
13.  
  Jonathan heard a deep rumbling sound in the ____.
_______________
14.  
  The burning of fossil fuels for ____ causes air pollution.


Assignment=Please click this website, then read and

 watch the animation 




After you have experimented with the site, please explain 

in your journal what lessons did you learn ?



Please read this article and answer the questions that follow
Forces Around Us 
By Cindy Grigg
  


1     Look around you, and chances are you'll see things moving. Cars move. People move. Elevators move up and down in tall buildings. Shopping carts move around in supermarkets. Balls fly through the air when they are thrown. You might not think about why these things move. Cars, elevators, and balls don't just move by themselves. Something is making them move. Forces make things move.


Main Idea and Details Graphic Organizer
Please copy this graphic organizer into your journal and complete it them there from the reading above


 2     A force is a push or a pull. If you had a heavy box to move across your room, you might push it or pull it. The force would be working on the box in the same direction. It wouldn't matter to the box if you pushed it or pulled it. The amount of force needed to move the box would be the same. The direction of the force would also be the same.
 3     When you push or pull a box, it is easy to see where the force is coming from. But it's harder to see forces at work when we think about a person or an animal moving. When you walk across the room, what force is making you move?

Please explain in your journal what a "force" is an a 2-3 sentence paragraph


 4     When you take a step, your foot is pushing down on the floor. That push is the force that makes your body move. When your foot pushes down on the floor, the floor pushes back. If the floor didn't push back, your foot wouldn't stop pushing down. You wouldn't go anywhere. You might end up standing in a hole.
 5     Have you ever tried to walk in deep snow? It's much harder to walk in snow than it is on solid ground. The snow is too soft; it can't push back as hard as the ground does.

Please copy this graphic organizer into your journal and complete it them there from the reading above

 6     Forces always occur in pairs. A push in one direction means something is pulling in the other direction. When you push a box across the floor in your room, what other forces are pulling on it?   
One is friction. Rub your hands together very fast. Do you feel heat? That heat is coming from the friction between your two hands. Whenever two things are rubbing against each other, friction is the force that slows them down. Tiny bits of matter on both surfaces rub against each other. As one surface rubs in one direction, the other surface rubs in the other direction. The two opposite forces create friction. Friction slows down the motion of both surfaces. Friction also makes heat. Some of the energy of motion changes into the energy of heat.

Main Idea and Details Graphic Organizer


Please copy this graphic organizer into your journal and complete it them there from the reading above

 8     Gravity is another force that pulls on the box when you push it across your room. You may already know that gravity is the force that pulls a ball to the ground when you throw it. Gravity is the force that pulls all things down toward the earth. If you jump up, gravity pulls you down. If you throw a ball, gravity pulls it to the ground. When you stand on a scale, the force of gravity is pushing down on you.
 


Please copy this graphic organizer into your journal and complete it them there from the reading above





9     As you push on the box, gravity is pulling on the box toward the ground. The two forces are not pushing and pulling in exactly opposite directions. Gravity is pulling straight down, and you are pushing sideways. The two forces are working against each other even though they are not directly opposite.
 10     Why do cars have wheels? Have you ever thought about that? A wheel rolls much easier than a box would. There is less friction between a rolling wheel and the ground than there would be between a flat surface like a box and the ground. That's why wheels were invented-they make things easier to move.
 11     Forces can be applied in different directions. Forces can be large or small. The direction a force is applied is the direction in which the object will move. Gravity is probably the most important force on earth. Forces are all around us!

Copyright © 2011 edHelper




Explain in your journal what you think a BETTER title for the reading could be and why? 



Please double click this web site below, and play the momentum 
game.
Please explain in your journal about the 7 lessons you 
learned playing the game



Please copy these questions into your journal and answer them there
_____________________________

Date ___________________
Forces Around Us


1.
What makes things move?




2.
A force is a ______.
  Push
  Pull
  Both A and B
  None of the above
3.
Forces always occur in ______.




4.
Complete this sentence: Whenever two things are rubbing against each other, friction ______.




5.
Where there is friction, there is ______.
  Fire
  Heat
  Noise
  Smoke
6.
What is the name of the force that pulls all things down toward the earth?
  Atomic force
  Gravity
  Friction
  Magnetic force
7.
Which of these would have less friction?
  A toy car with wheels rolling across the floor
  A rock being pushed across the sidewalk
8.
An object will move ______.
  Opposite the direction the force is applied
  In the direction the force is applied
  Both A and B






 _____________________________

Date ___________________
Forces Around Us
Please summarize what you have learned about force in a 2-4 sentence paragraph in your journal








_____________________________

Date ___________________
Forces Around Us
Describe in your own words the force of friction in a 2-4 sentence paragraph in your journal


Please copy these questions into your journal and answer them there





Date ___________________
Complete each sentence using the words in the word list.


Acceleration
Distance
Gravity
Speed

Equilibrium
Inertia
Energy
force


_______________
15.  
___  _ pulls things down while gravity support force pushes things up.
_______________
16.  
  You must use ____ to move the heavy box.
_______________
17.  
__  __ from the sun causes the ocean water to evaporate.
_______________
18.  
  The ____ on the moon is less it is on earth.
_______________
19.  
  Using the highway map, Miss Ranft can to find the ____ from New York City to Los Angeles.
_______________
20.  
_  ___ is a property of matter.
_______________
21.  
  Radiation releases ____ from atoms that can be useful, and dangerous.
_______________
22.  
  Mrs. Jurries lost her ____ along with her hearing due to an ear infection
_______________
23.  
  Is the earth's ____ from other planets and galaxies measured in miles or light years?
_______________
24.  
  The car was driven at a rapid ____.(adj)
_______________
25.  
  Sport cars tend to have faster ____ than your compact sedan.
_______________
26.  
  Heat is a type of ____.
_______________
27.  
  The ecosystem took some time to return to its natural ____.
_______________
28.  
  In science class, we learned about centripetal ____.
_______________
29.  
  Solar and wind power are two sources of renewable ____.


Please copy this cloze activity into your journal and answer it there
Forces Around Us 
By Cindy Grigg
  




straight
same
earth
amount


against
person
body
directions


direction
deep
than
whenever


foot
large
opposite
even


Directions:  Fill in each blank with the word that best completes the reading comprehension.

     Look around you, and chances are you'll see things moving. Cars move. People move. Elevators move up and down in tall buildings. Shopping carts move around in supermarkets. Balls fly through the air when they are thrown. You might not think about why these things move. Cars, elevators, and balls don't just move by themselves. Something is making them move. Forces make things move.
     A force is a push or a pull. If you had a heavy box to move across your room, you might push it or pull it. The force would be working on the box in the (1)  _______________________   direction. It wouldn't matter to the box if you pushed it or pulled it. The (2)  _______________________   of force needed to move the box would be the same. The direction of the force would also be the same.
     When you push or pull a box, it is easy to see where the force is coming from. But it's harder to see forces at work when we think about a(3)  _______________________   or an animal moving. When you walk across the room, what force is making you move?
     When you take a step, your foot is pushing down on the floor. That push is the force that makes your (4)  _______________________   move. When your(5)  _______________________   pushes down on the floor, the floor pushes back. If the floor didn't push back, your foot wouldn't stop pushing down. You wouldn't go anywhere. You might end up standing in a hole.
     Have you ever tried to walk in (6)  _______________________   snow? It's much harder to walk in snow than it is on solid ground. The snow is too soft; it can't push back as hard as the ground does.
     Forces always occur in pairs. A push in one direction means something is pulling in the other direction. When you push a box across the floor in your room, what other forces are pulling on it?
     One is friction. Rub your hands together very fast. Do you feel heat? That heat is coming from the friction between your two hands.(7)  _______________________   two things are rubbing against each other, friction is the force that slows them down. Tiny bits of matter on both surfaces rub against each other. As one surface rubs in one (8)  _______________________  , the other surface rubs in the other direction. The two opposite forces create friction. Friction slows down the motion of both surfaces. Friction also makes heat. Some of the energy of motion changes into the energy of heat.
     Gravity is another force that pulls on the box when you push it across your room. You may already know that gravity is the force that pulls a ball to the ground when you throw it. Gravity is the force that pulls all things down toward the earth. If you jump up, gravity pulls you down. If you throw a ball, gravity pulls it to the ground. When you stand on a scale, the force of gravity is pushing down on you.
     As you push on the box, gravity is pulling on the box toward the ground. The two forces are not pushing and pulling in exactly(9)  _______________________   (10)  _______________________  . Gravity is pulling (11)  _______________________   down, and you are pushing sideways. The two forces are working (12)  _______________________   each other (13)  _______________________   though they are not directly opposite.
     Why do cars have wheels? Have you ever thought about that? A wheel rolls much easier (14)  _______________________   a box would. There is less friction between a rolling wheel and the ground than there would be between a flat surface like a box and the ground. That's why wheels were invented-they make things easier to move.
     Forces can be applied in different directions. Forces can be (15)  _______________________   or small. The direction a force is applied is the direction in which the object will move. Gravity is probably the most important force on (16)  _______________________  . Forces are all around us!
 

Copyright © 2011 edHelper
 Please copy these questions into your journal and answer them there





 _____________________________

Date ___________________
Forces Around Us


1.
What makes things move?




2.
A force is a ______.
  Push
  Pull
  Both A and B
  None of the above
3.
Forces always occur in ______.




4.
Complete this sentence: Whenever two things are rubbing against each other, friction ______.




5.
Where there is friction, there is ______.
  Noise
  Fire
  Heat
  Smoke
6.
What is the name of the force that pulls all things down toward the earth?
  Magnetic force
  Atomic force
  Friction
  Gravity
7.
Which of these would have less friction?
  A toy car with wheels rolling across the floor
  A rock being pushed across the sidewalk
8.
An object will move ______.
  Opposite the direction the force is applied
  In the direction the force is applied
  Both A and B




Please copy these questions into your journal and answer them there





Date ___________________
Complete each sentence using the words in the word list.

Displacement
Distance
Gravity
force

Acceleration
Inertia
Energy
Mass


_______________
30.  
   She was pigeon-toed and her feet hurt when she walked any ____.
_______________
31.  
  Being a long ____ runner, Jill won the race effortlessly.
_______________
32.  
__  __ pulls things down while gravity support force pushes things up.
_______________
33.  
  The rocks caused ____ in the beaker of water.
_______________
34.  
  When his parents took him to his first Catholic ____, the stained glass windows in the cathedral awed him.
_______________
35.  
  A generator changes mechanical or heat ____ into electricity.
_______________
36.  
  The planets are held in place around the sun because of the sun's ____.
_______________
37.  
  The greater the ____ or speed, the greater the kinetic energy.
_______________
38.  
  The ____ of the explosion in the rocket's engine during the launch sent it into the air.
_______________
39.  
  The more ____ two objects have the greaterthe force of gravity is between them.
_______________
40.  
  An example of ____ is to run faster at the end of a race.
_______________
41.  
  With no ____ out in space, the astronauts will feel a type of emptiness while in the shuttle.
_______________
42.  
  Centrifugal force is the ____ of a body moving in a circle.
_______________
43.  
  Use the highway map, Matthew, to find the ____ from New York City to Los Angeles.





Please read this article and answer the questions that follow



Force and Motion 
By Sharon Fabian
  


1     Force and motion describe everyday things that are happening all the time. Hundreds of times every day, you use force and motion. Did you just pick up a pencil? -- force and motion. Did you turn a page? -- force and motion. Raise your hand? Kick the desk in front of you? Pack your backpack? All of these are examples of force and motion.
 2     Out on the playground you can see even bigger and better examples of force and motion. Climbing, jumping, running, chasing, throwing, and sliding all use force and motion.
 3     Force and motion are also parts of a complicated branch of science, called physics. Now that you know what force and motion are, the next thing that you should know are some definitions.
 4     The scientific definition of force is a push or a pull. When you throw a baseball, you are pushing it through the air. When you pick up a baseball bat you are pulling it up from the ground. When you hit the ball, you use both pushing and pulling motions.
 5     Motion is another word with a scientific meaning. Motion means moving something from one place to another. When you used force to swing the bat and hit the baseball, they both moved from one place to another. That's what motion is. In fact, the word motion is a form of the word move.
 6     Let's stick with our baseball example for a little bit longer. Some kids can hit a baseball harder than others can. You could say that their baseball travels at a faster rate.Speed is a scientific term that means the rate of motion, or how fast something travels.
 7     OK, enough about baseball. Now think about rocks. Why can you throw a little pebble farther than you can throw a huge boulder? The boulder is heavier; it has more weight.
 8     The Earth's gravity causes everything on Earth to have weight. Gravity is a force that pulls everything toward the center of the Earth. Gravity is holding both the pebble and the boulder down, at the same time that you are trying to throw them. Gravity is a force acting against your force. Gravity's force is stronger on heavier objects. That's why it is not too hard to throw the pebble, but very hard to throw the boulder. Weight is the measure of gravity's force. Since gravity is holding the boulder with more force than the pebble, the boulder has more weight.
 9     Force, motion, speed, gravity, and weight -- everyday words with special meanings in the science called physics.

Copyright © 2011 edHelper






Please copy these questions into your journal and answer them there
 _____________________________

Date ___________________
Force and Motion


1.
Force and motion are parts of a branch of science called
  Earth science
  Geology
  Physics
  Biology
2.
________ is the measure of gravity's force.
  Gravity
  Speed
  Force
  Weight
3.
________ is the force that pulls everything toward the center of the earth.
  Speed
  Force
  Gravity
  Weight
4.
________ means rate of motion, or how fast something is moving.
  Speed
  Gravity
  Weight
  Force
5.
Climbing a hill is an example of force and motion.
  True
  False
6.
Throwing a Frisbee is an example of force and motion.
  True
  False
7.
Ice-skating is another example of force and motion.
  True
  False
8.
List four more examples of force and motion that are not mentioned in this article.






Please explain in your journal what  force  is .

Please explain in your journal what  motion  is .

Please explain in your journal what speed    is .

Please explain in your journal what gravity   is .


Please explain in your journal what  weight  is .





Explain in your journal what you think a BETTER title for the reading could be and why? 





Please copy these questions into your journal and answer them there





Date ___________________
Complete each sentence using the words in the word list.

Distance
Energy
force


Gravity
Speed
Mass



_______________
44.  
  John was so lazy he rarely mustered enough ____ to walk more than five steps at a time!
_______________
45.  
  Although the horse had been bred for ____, he failed to place in any of his races.
_______________
46.  
  The sky was alight with a red glow as the fire raged in the ____.
_______________
47.  
They're going to overtake us if we don't ____ up.
_______________
48.  
  The skyline is easily discernible even at a ____ of several miles.
_______________
49.  
   Heat ____ can be produced by rubbing your hands together.
_______________
50.  
  There is less ____ between Johnathan and I than between Elisabeth and I.
_______________
51.  
  My ____ is equal to the distance I traveled divided by the time it took me to go that far.
_______________
52.  
  Density is the amount of ____ in a given space.
_______________
53.  
  The more mass two objects have the greaterthe ____ of gravity is between them.
_______________
54.  
__  __ is the force that holds us on the ground.
_______________
55.  
  186,000 miles per second, 300,000 kilometers per second, the ____ that light travels in a vacuum is called light speed.
_______________
56.  
  That ____ of stone became a meteor when it entered our atmosphere.
_______________
57.  
  The more weight you increase causes the ____ to increase also.



Please copy this cloze activity into your journal and answer it there
Force and Motion
By Sharon Fabian
  


move
even
moving
measure


meaning
describe
term
words


raise
word
force
through


meanings
everyday
moved
another


center
faster
scientific


Directions:  Fill in each blank with the word that best completes the reading comprehension.

     Force and motion (1)  _______________________   everyday things that are happening all the time. Hundreds of times every day, you use force and motion. Did you just pick up a pencil? -- force and motion. Did you turn a page? -- (2)  _______________________   and motion. (3)  _______________________   your hand? Kick the desk in front of you? Pack your backpack? All of these are examples of force and motion.
     Out on the playground you can see (4)  _______________________   bigger and better examples of force and motion. Climbing, jumping, running, chasing, throwing, and sliding all use force and motion.
     Force and motion are also parts of a complicated branch of science, called physics. Now that you know what force and motion are, the next thing that you should know are some definitions.
     The scientific definition of force is a push or a pull. When you throw a baseball, you are pushing it (5)  _______________________   the air. When you pick up a baseball bat you are pulling it up from the ground. When you hit the ball, you use both pushing and pulling motions.
     Motion is another word with a (6)  _______________________   (7)  _______________________  . Motion means (8)  _______________________   something from one place to(9)  _______________________  . When you used force to swing the bat and hit the baseball, they both (10)  _______________________   from one place to another. That's what motion is. In fact, the (11)  _______________________   motion is a form of the word (12)  _______________________  .
     Let's stick with our baseball example for a little bit longer. Some kids can hit a baseball harder than others can. You could say that their baseball travels at a (13)  _______________________   rate. Speed is a scientific (14)  _______________________   that means the rate of motion, or how fast something travels.
     OK, enough about baseball. Now think about rocks. Why can you throw a little pebble farther than you can throw a huge boulder? The boulder is heavier; it has more weight.
     The Earth's gravity causes everything on Earth to have weight. Gravity is a force that pulls everything toward the (15)  _______________________   of the Earth. Gravity is holding both the pebble and the boulder down, at the same time that you are trying to throw them. Gravity is a force acting against your force. Gravity's force is stronger on heavier objects. That's why it is not too hard to throw the pebble, but very hard to throw the boulder. Weight is the (16)  _______________________   of gravity's force. Since gravity is holding the boulder with more force than the pebble, the boulder has more weight.
     Force, motion, speed, gravity, and weight -- (17)  _______________________   (18)  _______________________   with special (19)  _______________________   in the science called physics.
 

Copyright © 2011 edHelper









Please read this article and answer the questions that follow

Newton's Three Laws of Motion 
By Sharon Fabian
  


1     Isaac Newton was born in 1643. His family was wealthy, so in some ways he had advantages over other kids his age, but in other ways he was disadvantaged. Isaac's father had died before Isaac was born, and he was raised by his grandmother and other relatives. At first he probably was not encouraged to learn much in school. He didn't pay attention in school, and was described as lazy. It was only after an uncle encouraged him to prepare to go on to college that he began to take an interest in school and to develop his talents. One of the skills he developed while still in school was making model machines, including clocks and windmills. In college he began studying the latest theories in math. Soon he was coming up with theories of his own, and today Sir Isaac Newton is well known for his three laws of motion as well as for other scientific breakthroughs.
 
Please copy this graphic organizer into your journal and complete it them there from the reading above













Please copy these questions into your journal and answer them there


Date ___________________
Complete each sentence using the words in the word list.

Acceleration
Distance
Energy
force

Friction
Inertia
Speed
Mass


_______________
58.  
   Comparing the lines of ____ showed us which magnet was stronger.
_______________
59.  
Oil is used to reduce ____ between metals parts in a car.
_______________
60.  
   Temperature is actually a measure of how much heat ____ there is.
_______________
61.  
_  ___ is conserved according to the las of conservation of mass.
_______________
62.  
   Force can be increased by increasing mass and or ____.
_______________
63.  
  Ellen saw lights in the ____.
_______________
64.  
  We asked neighbors to sign Mr. Smith's petition to get ____ bumps on his street.
_______________
65.  
  He used brute ____ to open the window when it was stuck.
_______________
66.  
  When you rub your hands together it creates ____ and friction creates heat.
_______________
67.  
 Volcanoes produce geothermal ____.
_______________
68.  
  Because of its ____, the elephant was difficult to move.
_______________
69.  
 Heat and ____ can force some electrons to leave one atom and move to another.
_______________
70.  
 When the volleyball player hit the ball, the ____ caused it to go in the opposite direction.
_______________
71.  
_ ___ between the two pieces of metal caused them to grow very hot.
_______________
72.  
 Skiing down hill at great ____ is so much fun.













2     Here are Sir Isaac Newton's three laws of motion.
 3     Law 1 - An object moving in a straight line will continue moving in a straight line, unless acted on by an outside force. Also, an object at rest will stay at rest. The word for this is inertia.
 4     Law 2 - Force will cause a change in the motion of an object. The change in motion depends on the amount of force and the mass of the object. There is a formula for this F=ma (force equals mass times acceleration).
 5     Law 3 - For each action, there is an equal and opposite reaction.
 
Please copy this graphic organizer into your journal and complete it them there from the reading above

6     These three laws will make more sense, and be a lot more interesting, if you do some experiments to demonstrate each law. Maybe Sir Isaac did some similar experiments when he was testing out his theories.




 7     To demonstrate the first law, you might want to try the old trick of pulling the tablecloth out from under the dishes on the table. If you do it just right, you will remove the table cloth without causing the dishes to crash to the floor. Then again, maybe you wouldn't want to try that one, even though Newton's first law says that objects at rest, like the dishes, will stay at rest.
 8     Another way to demonstrate inertia is to show what can happen when you don't wear your seat belt. A safe way to demonstrate this is with a small toy truck, a clay figure, a ramp, and a brick. Place the little clay figure in the toy truck. Place the brick just a short distance past the end of the ramp. The toy truck can roll down the ramp until it hits the brick. When it hits the brick, the truck will stop suddenly, but the clay figure will keep moving forward and fly out of the truck because of inertia.
 






Newton's First Law of Motion

Newton's First Law

In a previous chapter of study, the variety of ways by which motion can be described (words, graphs, diagrams, numbers, etc.) was discussed. In this unit (Newton's Laws of Motion), the ways in which motion can be explained will be discussed. Isaac Newton (a 17th century scientist) put forth a variety of laws that explain why objects move (or don't move) as they do. These three laws have become known as Newton's three laws of motion. The focus of Lesson 1 is Newton's first law of motion - sometimes referred to as the law of inertia.
Newton's first law of motion is often stated as
An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

 

There are two parts to this statement - one that predicts the behavior of stationary objects and the other that predicts the behavior of moving objects. The two parts are summarized in the following diagram.

The behavior of all objects can be described by saying that objects tend to "keep on doing what they're doing" (unless acted upon by an unbalanced force). If at rest, they will continue in this same state of rest. If in motion with an eastward velocity of 5 m/s, they will continue in this same state of motion (5 m/s, East). If in motion with a leftward velocity of 2 m/s, they will continue in this same state of motion (2 m/s, left). The state of motion of an object is maintained as long as the object is not acted upon by an unbalanced force. All objects resist changes in their state of motion - they tend to "keep on doing what they're doing."

Suppose that you filled a baking dish to the rim with water and walked around an oval track making an attempt to complete a lap in the least amount of time. The water would have a tendency to spill from the container during specific locations on the track. In general the water spilled when:
  • the container was at rest and you attempted to move it
  • the container was in motion and you attempted to stop it
  • the container was moving in one direction and you attempted to change its direction.
The water spills whenever the state of motion of the container is changed. The water resisted this change in its own state of motion. The water tended to "keep on doing what it was doing." The container was moved from rest to a high speed at the starting line; the water remained at rest and spilled onto the table. The container was stopped near the finish line; the water kept moving and spilled over container's leading edge. The container was forced to move in a different direction to make it around a curve; the water kept moving in the same direction and spilled over its edge. The behavior of the water during the lap around the track can be explained by Newton's first law of motion.

Everyday Applications of Newton's First Law

There are many applications of Newton's first law of motion. Consider some of your experiences in an automobile. Have you ever observed the behavior of coffee in a coffee cup filled to the rim while starting a car from rest or while bringing a car to rest from a state of motion? Coffee "keeps on doing what it is doing." When you accelerate a car from rest, the road provides an unbalanced force on the spinning wheels to push the car forward; yet the coffee (that was at rest) wants to stay at rest. While the car accelerates forward, the coffee remains in the same position; subsequently, the car accelerates out from under the coffee and the coffee spills in your lap. On the other hand, when braking from a state of motion the coffee continues forward with the same speed and in the same direction, ultimately hitting the windshield or the dash. Coffee in motion stays in motion.
Have you ever experienced inertia (resisting changes in your state of motion) in an automobile while it is braking to a stop? The force of the road on the locked wheels provides the unbalanced force to change the car's state of motion, yet there is no unbalanced force to change your own state of motion. Thus, you continue in motion, sliding along the seat in forward motion. A person in motion stays in motion with the same speed and in the same direction ... unless acted upon by the unbalanced force of a seat belt. Yes! Seat belts are used to provide safety for passengers whose motion is governed by Newton's laws. The seat belt provides the unbalanced force that brings you from a state of motion to a state of rest. Perhaps you could speculate what would occur when no seat belt is used.

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After you have experimented with the site, please explain 

in your journal what lessons did you learn ?




 
There are many more applications of Newton's first law of motion. Several applications are listed below. Perhaps you could think about the law of inertia and provide explanations for each application.
  • Blood rushes from your head to your feet while quickly stopping when riding on a descending elevator.
  • The head of a hammer can be tightened onto the wooden handle by banging the bottom of the handle against a hard surface.
  • A brick is painlessly broken over the hand of a physics teacher by slamming it with a hammer. (CAUTION: do not attempt this at home!)
  • To dislodge ketchup from the bottom of a ketchup bottle, it is often turned upside down and thrusted downward at high speeds and then abruptly halted.
  • Headrests are placed in cars to prevent whiplash injuries during rear-end collisions.
  • While riding a skateboard (or wagon or bicycle), you fly forward off the board when hitting a curb or rock or other object that abruptly halts the motion of the skateboard.
Assignment=Please click this website, then read and watch the animation 


After you have experimented with the site, please explain 

in your journal what lessons did you learn ?


Try This At Home

Acquire a metal coat hanger for which you have permission to destroy. Pull the coat hanger apart. Using duct tape, attach two tennis balls to opposite ends of the coat hanger as shown in the diagram at the right. Bend the hanger so that there is a flat part that balances on the head of a person. The ends of the hanger with the tennis balls should hang low (below the balancing point). Place the hanger on your head and balance it. Then quickly spin in a circle. What do the tennis balls do?

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9     For the second law, there are many demonstrations that you can do. Anything that involves using a force to move an object would demonstrate Newton's second law. You might want to try an experiment in which you change the amount of force that you use, or change the mass of the objects that you try to move. For example, you could set up a little seesaw, made from a ruler balanced on a pencil. Try objects of different weights at the one end, and drop something on the other end to see which object moves the farthest. Or, try dropping the objects from different heights.






Please copy this graphic organizer into your journal and complete it them there from the reading above
 10     The third law is fun to demonstrate. One way is with a basketball and roller skates. Two kids, each wearing roller skates, stand facing each other and throw a basketball back and forth. As each kid pushes the basketball forward, he will roll backwards on his skates. That is the equal and opposite reaction described in the third law. You can also build a balloon racer to demonstrate the third law. Tie a string between two chairs, pretty far apart. Put an empty pen case or a section of a straw on the string so that it can slide along the string. Now blow up a balloon but don't tie it. Carefully tape the balloon to the pen case or straw, then let go. The action of the air shooting out of the balloon causes a reaction of the balloon racing across the string towards the opposite end.
 


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Newton's Third Law of Motion

Newton's Third Law

A force is a push or a pull upon an object that results from its interaction with another object. Forces result from interactions! As discussed in Lesson 2, some forces result from contact interactions (normal, frictional, tensional, and applied forces are examples of contact forces) and other forces are the result of action-at-a-distance interactions (gravitational, electrical, and magnetic forces). According to Newton, whenever objects A and B interact with each other, they exert forces upon each other. When you sit in your chair, your body exerts a downward force on the chair and the chair exerts an upward force on your body. There are two forces resulting from this interaction - a force on the chair and a force on your body. These two forces are called action and reaction forces and are the subject of Newton's third law of motion. Formally stated, Newton's third law is:
For every action, there is an equal and opposite reaction.
The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. Forcesalways come in pairs - equal and opposite action-reaction force pairs.
A variety of action-reaction force pairs are evident in nature. Consider the propulsion of a fish through the water. A fish uses its fins to push water backwards. But a push on the water will only serve to accelerate the water. Since forces result from mutual interactions, the water must also be pushing the fish forwards, propelling the fish through the water. The size of the force on the water equals the size of the force on the fish; the direction of the force on the water (backwards) is opposite the direction of the force on the fish (forwards). For every action, there is an equal (in size) and opposite (in direction) reaction force. Action-reaction force pairs make it possible for fish to swim.
Consider the flying motion of birds. A bird flies by use of its wings. The wings of a bird push air downwards. Since forces result from mutual interactions, the air must also be pushing the bird upwards. The size of the force on the air equals the size of the force on the bird; the direction of the force on the air (downwards) is opposite the direction of the force on the bird (upwards). For every action, there is an equal (in size) and opposite (in direction) reaction. Action-reaction force pairs make it possible for birds to fly.
Consider the motion of a car on the way to school. A car is equipped with wheels that spin in a clockwise direction. As the wheels spin clockwise, they grip the road and push the road backwards. Since forces result from mutual interactions, the road must also be pushing the wheels forward. The size of the force on the road equals the size of the force on the wheels (or car); the direction of the force on the road (backwards) is opposite the direction of the force on the wheels (forwards). For every action, there is an equal (in size) and opposite (in direction) reaction. Action-reaction force pairs make it possible for cars to move along a roadway surface.
 

 

Check Your Understanding

1. While driving down the road, a firefly strikes the windshield of a bus and makes a quite obvious mess in front of the face of the driver. This is a clear case of Newton's third law of motion. The firefly hit the bus and the bus hits the firefly. Which of the two forces is greater: the force on the firefly or the force on the bus?

 

 

Check your understanding answer

Trick Question! Each force is the same size. For every action, there is an equal ... (equal!). The fact that the firefly splatters only means that with its smaller mass, it is less able to withstand the larger acceleration resulting from the interaction. Besides, fireflies have guts and bug guts have a tendency to besplatterable. Windshields don't have guts. There you have it.

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2. For years, space travel was believed to be impossible because there was nothing that rockets could push off of in space in order to provide the propulsion necessary to accelerate. This inability of a rocket to provide propulsion is because ...
a. ... space is void of air so the rockets have nothing to push off of.
b. ... gravity is absent in space.
c. ... space is void of air and so there is no air resistance in space.
d. ... nonsense! Rockets do accelerate in space and have been able to do so for a long time.

 

Check your understanding answer

It is a common misconception that rockets are unable to accelerate in space. The fact is that rockets do accelerate. There is indeed nothing for rockets to push off of in space - at least nothing which is external to the rocket. But that's no problem for rockets. Rockets are able to accelerate due to the fact that they burn fuel and push the exhaust gases in a direction opposite the direction which they wish to accelerate.

 
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3. Many people are familiar with the fact that a rifle recoils when fired. This recoil is the result of action-reaction force pairs. A gunpowder explosion creates hot gases that expand outward allowing the rifle to push forward on the bullet. Consistent with Newton's third law of motion, the bullet pushes backwards upon the rifle. The acceleration of the recoiling rifle is ...
a. greater than the acceleration of the bullet.
b. smaller than the acceleration of the bullet.
c. the same size as the acceleration of the bullet.

 Check your understanding answer
The force on the rifle equals the force on the bullet. Yet, acceleration depends on both force and mass. The bullet has a greater acceleration due to the fact that it has a smaller mass. Remember: acceleration and mass are inversely proportional.

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4. In the top picture (below), Kent Budgett is pulling upon a rope that is attached to a wall. In the bottom picture, the Kent is pulling upon a rope that is attached to an elephant. In each case, the force scale reads 500 Newton. Kent is pulling ...
a. with more force when the rope is attached to the wall.
b. with more force when the rope is attached to the elephant.
c. the same force in each case.


Check your understanding answer

Kent is pulling with 500 N of force in each case. The rope transmits the force from Kent to the wall (or to the elephant) and vice versa. Since the force of Kent pulling on the wall and the wall pulling on Kent are action-reaction force pairs, they must have equal magnitudes. Inanimate objects such as walls can push and pull.


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11     If you don't feel like doing experiments, you can always observe Newton's laws of motion in another location, an amusement park. Roller coasters, merry-go-rounds, and bumper cars all follow Newton's three laws of motion, and are part of the science of force and motion.

Copyright © 2011 edHelper




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Please copy these questions into your journal and answer them there






Date ___________________
Complete each sentence using the words in the word list.


Acceleration
Inertia
Energy
force

Friction
Gravity
Speed
Mass


_______________
73.  
_ ___ is conserved according to the las of conservation of mass.
_______________
74.  
 When Charles gets home from school and plops down on the couch, he does not have much ____ to get up and do the list his mother left for him.
_______________
75.  
 The tide rises and falls because of the pull of the moon's ____.
_______________
76.  
_ ___ divided by volume equals density.
_______________
77.  
  This flow of ____ is an energy chain.
_______________
78.  
_ ___ prevents sneakers from slipping on a gym floor.
_______________
79.  
 The ____ of the wind made me fall back.
_______________
80.  
  Will the ____ of gravity pull the comet to Earth?
_______________
81.  
_ ___ keeps the dishes on the table when I pull the table cloth off.
_______________
82.  
  Weightlessness in space is caused by the lack of ____.
_______________
83.  
  We asked neighbors to sign Mrs. Leftwich's petition to get ____ bumps on her street.
_______________
84.  
  When the fire alarm rang, the visitors lingered in the hall because they did not realize the ____ of the situation.
_______________
85.  
  Solar ____ can be converted to electricity on both small and large scale.
_______________
86.  
 The jet was unable to take off because it failed to reach proper ____.





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Copy these questions into your journal and answer them there
_____________________________

Date ___________________
Newton's Three Laws of Motion


1.
Sir Isaac Newton's only discovery was the three laws of motion.
  True
  False
2.
According to the first law, an object that is sitting still will stay that way.
  True
  False
3.
The formula F=ma means "force equals motion times acceleration."
  True
  False
4.
The third law says that some actions will produce an equal and opposite reaction.
  True
  False
5.
Sir Isaac Newton probably never conducted any experiments.
  True
  False
6.
One word that sums up the first law is
  Force
  Inertia
  Acceleration
  Motion
7.
Bumper cars are an example of Newton's third law. Explain.




8.
A roller coaster is a good example of more than one of Newton's laws of motion. Explain.









Copy this cloze assignment below into your journal and answer them there
Newton's Three Laws of Motion 
By Sharon Fabian
  



developed
    math
ruler
formula


location
causes
motion
testing


prepare
section
cause
wealthy


inertia
which
develop
born


case
causing


Directions:  Fill in each blank with the word that best completes the reading comprehension.

     Isaac Newton was born in 1643. His family was (1)  _______________________  , so in some ways he had advantages over other kids his age, but in other ways he was disadvantaged. Isaac's father had died before Isaac was (2)  _______________________  , and he was raised by his grandmother and other relatives. At first he probably was not encouraged to learn much in school. He didn't pay attention in school, and was described as lazy. It was only after an uncle encouraged him to (3)  _______________________   to go on to college that he began to take an interest in school and to (4)  _______________________   his talents. One of the skills he (5)  _______________________   while still in school was making model machines, including clocks and windmills. In college he began studying the latest theories in (6)  _______________________  . Soon he was coming up with theories of his own, and today Sir Isaac Newton is well known for his three laws of motion as well as for other scientific breakthroughs.
     Here are Sir Isaac Newton's three laws of motion.
     Law 1 - An object moving in a straight line will continue moving in a straight line, unless acted on by an outside force. Also, an object at rest will stay at rest. The word for this is inertia.
     Law 2 - Force will (7)  _______________________   a change in the motion of an object. The change in motion depends on the amount of force and the mass of the object. There is a(8)  _______________________   for this F=ma (force equals mass times acceleration).
     Law 3 - For each action, there is an equal and opposite reaction.
     These three laws will make more sense, and be a lot more interesting, if you do some experiments to demonstrate each law. Maybe Sir Isaac did some similar experiments when he was(9)  _______________________   out his theories.
     To demonstrate the first law, you might want to try the old trick of pulling the tablecloth out from under the dishes on the table. If you do it just right, you will remove the table cloth without(10)  _______________________   the dishes to crash to the floor. Then again, maybe you wouldn't want to try that one, even though Newton's first law says that objects at rest, like the dishes, will stay at rest.
     Another way to demonstrate (11)  _______________________   is to show what can happen when you don't wear your seat belt. A safe way to demonstrate this is with a small toy truck, a clay figure, a ramp, and a brick. Place the little clay figure in the toy truck. Place the brick just a short distance past the end of the ramp. The toy truck can roll down the ramp until it hits the brick. When it hits the brick, the truck will stop suddenly, but the clay figure will keep moving forward and fly out of the truck because of inertia.
     For the second law, there are many demonstrations that you can do. Anything that involves using a force to move an object would demonstrate Newton's second law. You might want to try an experiment in which you change the amount of force that you use, or change the mass of the objects that you try to move. For example, you could set up a little seesaw, made from a(12)  _______________________   balanced on a pencil. Try objects of different weights at the one end, and drop something on the other end to see (13)  _______________________   object moves the farthest. Or, try dropping the objects from different heights.
     The third law is fun to demonstrate. One way is with a basketball and roller skates. Two kids, each wearing roller skates, stand facing each other and throw a basketball back and forth. As each kid pushes the basketball forward, he will roll backwards on his skates. That is the equal and opposite reaction described in the third law. You can also build a balloon racer to demonstrate the third law. Tie a string between two chairs, pretty far apart. Put an empty pen (14)  _______________________   or a (15)  _______________________   of a straw on the string so that it can slide along the string. Now blow up a balloon but don't tie it. Carefully tape the balloon to the pen case or straw, then let go. The action of the air shooting out of the balloon(16)  _______________________   a reaction of the balloon racing across the string towards the opposite end.
     If you don't feel like doing experiments, you can always observe Newton's laws of motion in another (17)  _______________________  , an amusement park. Roller coasters, merry-go-rounds, and bumper cars all follow Newton's three laws of (18)  _______________________  , and are part of the science of force and motion.
 

Copyright © 2011 edHelper




Please copy these questions into your journal and answer them there






Date ___________________
Complete each sentence using the words in the word list.

Displacement
Friction
Inertia
force

Acceleration
Distance
Speed
Mass


_______________
87.  
   Many rocks cause ____ in lakes and oceans.
_______________
88.  
  The ____ of the magnet allowed us to pick up metal objects.
_______________
89.  
  You have ____ when your body resists change.
_______________
90.  
   We gazed at the craggy mountaintop in the ____.
_______________
91.  
  New ____ limits are not always easily enforceable.
_______________
92.  
 Three types of ____ are rolling, sliding, and fluid (air).
_______________
93.  
 Weight is different from mass in that mass does not involve gravitational ____.
_______________
94.  
 A cannon ball has more ____ than a beach ball.
_______________
95.  
 The drivers were oblivious of the ____ limit as they rushed to the hospital.
_______________
96.  
 The invention of the computer caused an ____ of changes in our world.
_______________
97.  
 We studied the ____ of celestial objects orbiting the sun.
_______________
98.  
 The ____ of the wind was breathtaking.
_______________
99.  
 Joe will change the ____ of his car by using the brakes.







 _____________________________

Date ___________________
(
Please write a sentence using each word in your journal.
1.
  
 inertia  


2.
  
 example  


3.
  
 math  


4.
   
formula  


5.
  
 seesaw  


6.
  
 testing  


7.
  
 interest  


8.
  
  wealthy  


9.
  
 formula  









Please read this article and answer the questions that follow






It's Dynamic! Force and Energy 
By Trista L. Pollard
  


1     According to Sir Isaac Newton, bodies at rest will remain at rest, and bodies in motion will remain in motion. However, in the science of dynamics,force and energy are important factors that can affect the motion of bodies. Force is the push or pull of an object that tends to produce acceleration of the body's motion in the direction of the force. Force also changes the size and shape of a body. There are four basic forces in nature. However, in relation to machines and vehicles, we will only talk about the forces related to gravity and motion. Gravity is the force of attraction between any two objects. This force depends on the mass or weight of each object and their distance from each other. Gravitational force is always attractive; however, over increasing distances, the force decreases, but it is still measurable. Gravity is the force that keeps all beings and objects on earth. If we traveled into space, we would experience an environment that has zero gravitational pull. Another concept related to gravity is free fall. Free fall occurs when objects fall downward toward earth due to earth's gravitational pull. If two different objects with different masses were in a free fall from the same height, they would have the same acceleration regardless of their masses. I wonder if a free falling feather and a bowling ball would reach the ground at the same time. I don't recommend trying this experiment; I was just wondering.
 





Please copy this graphic organizer into your journal and complete it them there from the reading above




2     Momentum is the force or speed of movement. This occurs when force is applied to an already moving object. Once the force is applied, the object's momentum may increase or decrease. When force is not applied to a moving body, its momentum will not change. Think about water flowing down a steep hill. As the water flows down the hill, it gains momentum to the point where its velocity or speed will increase. When your little brother goes running across the grass and tries to run up the hill to the playground, you will notice his momentum decrease as the hill becomes steeper. As he runs toward the top, his velocity will decrease, and he will probably be tired once he gets to the playground.


Please copy this graphic organizer into your journal and complete it them there from the reading above


 3     There are other forces that affect the movement of objects. Friction is a force that resists the movement between two objects that are touching. Increasing the friction on a moving object will decrease the object's velocity. An example would be when you go "skating" in your socks on your kitchen floor. Since there is very little friction, you should move rather quickly. However, as soon as you try to continue your sock skating on the rug, you will notice that your motion almost comes to a halt. The friction between your socks and the rug is greater than the friction was between your socks and the smooth kitchen floor. Therefore, your motion has decreased. Tension is another type of force that involves objects like springs. Tension is the force that is exerted or produced by a stretched object. The tighter the object is pulled, the greater the tension. Sometimes the tension becomes too great causing the object to break. Springs, due to their design, are able to withstand huge amounts of tension. It is for this reason they are used as parts of machines and other objects. Now that we have talked about force, we will talk about energy.



Please copy this graphic organizer into your journal and complete it them there from the reading above


 4     Energy is the ability of an object or being to do work or to make something happen. The following are different forms of energy: heat, light, sound, electrical, chemical, and mechanical. When it comes to motion, two forms of energy are very important. Potential energy is the stored energy in an object that when released can change into another form of energy. Kinetic energy is the energy of motion, and it depends on the mass of the object and the object's speed or velocity. Imagine the basketball you left at the top of the stairs in your house. Although that basketball is at rest, it has potential energy. This means that it has the potential to move. Now if a force (your sister's foot) happens to push the ball (that's right, she kicked it down the stairs), the basketball potential energy has turned into kinetic energy. The basketball's energy of position has changed to energy of motion. When the basketball meets a force that will cause it to rest, its energy of motion will change back into energy of position.




Please copy this graphic organizer into your journal and complete it them there from the reading above


 5     Another example of changes between potential and kinetic energy is a playground swing. As you sit on the swing, flying back and forth in the air, you probably noticed that as you swung higher, your motion became faster. When your body flies upward, the swing's kinetic energy is continuously being changed to potential energy. This is why you may appear to slow down as you reach the top of your swing. The higher you go, the greater the potential energy. As you make your way downward, the increased potential energy will convert to an increased amount of kinetic energy. The whole process begins again, until you get tired of swinging.

Please copy this graphic organizer into your journal and complete it them there from the reading above


 6     Although energy can be converted from one form to another, it can not be created or destroyed. This principle is the Law of Conservation of Energy . Simply put, if an object is not affected by an outside force, then the energy within that object remains constant. The laws of motion and the principles of force and energy are important to keep in mind when we begin to study how machines and vehicles move in our world. As we journey through the unit of transportation these laws and principles will reemerge like road signs on an endless highway.



Explain in your journal what you think a BETTER title for the reading could be and why? 


Please explain what the "Law of Conservation of Energy" is in your journal in a 3-5 sentence paragraphCopyright © 2011 edHelper






_____________________________

Date ___________________
It's Dynamic! Force and Energy


1.
Gravity is ____.
  The energy of two objects as they move
  The weight of two objects when they are weighed together
  The force of attraction between two masses
  The force of repulsion between two masses
2.
Force only changes the motion of an object or body.
  False
  True
3.
The force or speed of movement is called ____.
  Momentum
  Energy
  Friction
  Velocity
4.
Compare and contrast potential energy with kinetic energy.




5.
Tension is the force that is ____.
  Produced by friction between two objects
  Produced by the energy of two objects
  Produced by the gravitational pull of two objects
  Produced by a stretched object
6.
Explain the Law of Conservation of Energy.




7.
Explain the relationship between free fall and gravity.




8.
Skating in your socks across your living room rug would produce less friction than skating across your kitchen floor in your socks.
  False
  True




Stopping Distance of a Hot Wheels Car

Consider the motion of a Hot Wheels car beginning from rest at an elevated position. The Hot Wheels car rolls down a hill and begins its motion across a level surface. Along the level surface, the Hot Wheels car collides with a box and skids to a stop over a given distance. How could work and energy be utilized to analyze the motion of the Hot Wheels car? Would the total mechanical energy of the Hot Wheels car be altered in the process of rolling down the incline or in the process of skidding to a stop? Or would the total mechanical energy of the Hot Wheels car merely be conserved during the entire motion?
Of course the answers to these questions begin by determining whether or not external forces are doing work upon the car. If external forces do work upon the car, the total mechanical energy of the car is not conserved; the initial amount of mechanical energy is not the same as the final amount of mechanical energy. On the other hand, if external forces do not do work upon the car, then the total mechanical energy is conserved; that is, mechanical energy is merely transformed from the form of potential energy to the form of kinetic energy while the total amount of the two forms remains unchanged.
While the Hot Wheels car moves along the incline, external forces do not do work upon it. This assumes that dissipative forces such as air resistance have a negligible affect on the car's motion. This is a reasonable assumption for the low speeds of the car and its streamline characteristics. Since external forces do not do work on the car, the total mechanical energy of the car is conserved while moving along the incline. As the work-energy bar charts in the animation below depict, energy is transformed from potential energy (the stored energy of position) to kinetic energy (the energy of motion). The car gains speed as it loses height. The bar chart also depicts the fact that the total amount of mechanical energy is always the same; when the two forms are added together, the sum is unchanging.
When the Hot Wheels car collides with the box and skids to a stop, external forces do a significant amount of work upon the car. The force of friction acts in the direction opposite the car's motion and thus does negative work upon the car. This negative works contributes to a loss in mechanical energy of the car. In fact, if 0.40 Joules of mechanical energy are lost, then -0.40 Joules of work are done upon the car. As this work is done, the mechanical energy of the car (in the form of kinetic energy) is transformed into non-mechanical forms of energy such as sound and heat.
Analyze the animation and use the principles of work and energy to answer the given questions.



Questions to Ponder:
1. Use energy conservation principles to determine the speed of a 0.050-kg Hot Wheels car that descends from a height of 0.60 meter to a height of 0.00 meter. Assume negligible air resistance.

***Since PE intitial = KE final (ie. all energy in the  form of height is converted to energy in the form of motion to 



Use this formula         m*g*h= 0.5*m*v^2


2. Use energy conservation principles to determine the speed of a 0.050-kg Hot Wheels car that descends halfway down a 0.60-meter high hill (i.e., to a height of 0.30 meters). Assume negligible air resistance.


3. If the mass of the Hot Wheels car was twice as great (0.100 kg), then what would be the speed at the bottom of the 0.60-meter high hill?


4. If the 0.050-kg Hot Wheels car is brought to a rest over a distance of 0.40 meters, then what is the magnitude of the frictional force acting upon the car?





_____________________________

Date ___________________
It's Dynamic! Force and Energy
Imagine You are a playground swing. Write a poem, story or rap in your journal that explains how you experience potential and kinetic energy.








 _____________________________

Date ___________________
It's Dynamic! Force and Energy
Create: Think about examples of friction that you see in your daily life. Write a poem tory or rap in your journalthat describes friction. Try to be creative in your descriptions.



Copy this cloze assignment below into your journal and answer them there
It's Dynamic! Force and Energy 
By Trista L. Pollard
  



withstand
acceleration
masses
convert


affected
increasing
traveled
upward


produce
increased
reemerge
electrical


produced
dynamics
converted
mass


gravity
increase
decreases
decrease


however
decreased


Directions:  Fill in each blank with the word that best completes the reading comprehension.

     According to Sir Isaac Newton, bodies at rest will remain at rest, and bodies in motion will remain in motion. However, in the science of(1)  _______________________  , force and energy are important factors that can affect the motion of bodies. Force is the push or pull of an object that tends to(2)  _______________________   acceleration of the body's motion in the direction of the force. Force also changes the size and shape of a body. There are four basic forces in nature. (3)  _______________________  , in relation to machines and vehicles, we will only talk about the forces related to gravity and motion.(4)  _______________________   is the force of attraction between any two objects. This force depends on the (5)  _______________________   or weight of each object and their distance from each other. Gravitational force is always attractive; however, over (6)  _______________________   distances, the force(7)  _______________________  , but it is still measurable. Gravity is the force that keeps all beings and objects on earth. If we (8)  _______________________   into space, we would experience an environment that has zero gravitational pull. Another concept related to gravity is free fall. Free fall occurs when objects fall downward toward earth due to earth's gravitational pull. If two different objects with different masses were in a free fall from the same height, they would have the same (9)  _______________________   regardless of their(10)  _______________________  . I wonder if a free falling feather and a bowling ball would reach the ground at the same time. I don't recommend trying this experiment; I was just wondering.
     Momentum is the force or speed of movement. This occurs when force is applied to an already moving object. Once the force is applied, the object's momentum may(11)  _______________________   or decrease. When force is not applied to a moving body, its momentum will not change. Think about water flowing down a steep hill. As the water flows down the hill, it gains momentum to the point where its velocity or speed will increase. When your little brother goes running across the grass and tries to run up the hill to the playground, you will notice his momentum decrease as the hill becomes steeper. As he runs toward the top, his velocity will (12)  _______________________  , and he will probably be tired once he gets to the playground.
     There are other forces that affect the movement of objects. Friction is a force that resists the movement between two objects that are touching. Increasing the friction on a moving object will decrease the object's velocity. An example would be when you go "skating" in your socks on your kitchen floor. Since there is very little friction, you should move rather quickly. However, as soon as you try to continue your sock skating on the rug, you will notice that your motion almost comes to a halt. The friction between your socks and the rug is greater than the friction was between your socks and the smooth kitchen floor. Therefore, your motion has (13)  _______________________  . Tension is another type of force that involves objects like springs. Tension is the force that is exerted or (14)  _______________________   by a stretched object. The tighter the object is pulled, the greater the tension. Sometimes the tension becomes too great causing the object to break. Springs, due to their design, are able to (15)  _______________________   huge amounts of tension. It is for this reason they are used as parts of machines and other objects. Now that we have talked about force, we will talk about energy.
     Energy is the ability of an object or being to do work or to make something happen. The following are different forms of energy: heat, light, sound, (16)  _______________________  , chemical, and mechanical. When it comes to motion, two forms of energy are very important. Potential energy is the stored energy in an object that when released can change into another form of energy. Kinetic energy is the energy of motion, and it depends on the mass of the object and the object's speed or velocity. Imagine the basketball you left at the top of the stairs in your house. Although that basketball is at rest, it has potential energy. This means that it has the potential to move. Now if a force (your sister's foot) happens to push the ball (that's right, she kicked it down the stairs), the basketball potential energy has turned into kinetic energy. The basketball's energy of position has changed to energy of motion. When the basketball meets a force that will cause it to rest, its energy of motion will change back into energy of position.
     Another example of changes between potential and kinetic energy is a playground swing. As you sit on the swing, flying back and forth in the air, you probably noticed that as you swung higher, your motion became faster. When your body flies (17)  _______________________  , the swing's kinetic energy is continuously being changed to potential energy. This is why you may appear to slow down as you reach the top of your swing. The higher you go, the greater the potential energy. As you make your way downward, the (18)  _______________________   potential energy will (19)  _______________________   to an increased amount of kinetic energy. The whole process begins again, until you get tired of swinging.
     Although energy can be (20)  _______________________   from one form to another, it can not be created or destroyed. This principle is the Law of Conservation of Energy . Simply put, if an object is not (21)  _______________________   by an outside force, then the energy within that object remains constant. The laws of motion and the principles of force and energy are important to keep in mind when we begin to study how machines and vehicles move in our world. As we journey through the unit of transportation these laws and principles will(22)  _______________________   like road signs on an endless highway.
 

Copyright © 2011 edHelper






_____________________________

Date ___________________

















POST TEST - Please copy into your journal and answer these questions there.
 Under what circumstances is an object accelerating?
· If an object is moving with constant speed, does it necessarily move with constant velocity?
· What is the acceleration of an object if it is moving with constant velocity of 400 m/s?
· What is the acceleration of an object thrown up in the air when it reaches its highest point?
· What happens to the acceleration of an object thrown straight up while it is rising?
· Under what circumstances is the net force acting on an object equal to zero?
· What is the net force acting on an object that is moving in a circle at constant speed?
· How does the acceleration of an object change with the net force acting on it?
· Why do you lurch forward in a bus that suddenly slows? Why do you lurch backward when it picks up speed?
· A force of gravity pulls downward on a book on a table. What force prevents the book from accelerating downward?
· Why does the action-reaction pair of forces in Newton’s Third Law not cancel?
· How does the force exerted by the Sun on the Earth as the Earth moves around the Sun compare to the force that the Earth exerts on the Sun?
· What property of an object refers to its resistance to change in state of motion?
· How does friction affect the net force on an object?
· How great is the force of friction compared with your push on a crate that doesn’t move on a level floor?
· If the mass of a sliding object is tripled while a constant net force is applied, by how much does the acceleration change?
· If the speed of a moving object is doubled, by how much does its kinetic energy change?
· What happens to the kinetic energy of an object that is thrown straight up in the air while the object is rising? Where does the kinetic energy go?
· An object is dropped from a certain height above the ground. In the absence of air resistance, how does the kinetic energy of the object just before it hits the ground compare with its potential energy when it was released?
· Describe the energy transformation of a swinging pendulum.




 _____________________________

Date ___________________
Newton's Three Laws of Motion

1.
Sir Isaac Newton's only discovery was the three laws of motion.
  True
  False
2.
According to the first law, an object that is sitting still will stay that way.
  True
  False
3.
The formula F=ma means "force equals motion times acceleration."
  True
  False
4.
The third law says that some actions will produce an equal and opposite reaction.
  True
  False
5.
Sir Isaac Newton probably never conducted any experiments.
  True
  False
6.
One word that sums up the first law is
  Inertia
  Acceleration
  Force
  Motion
7.
Bumper cars are an example of Newton's third law. Explain.




8.
A roller coaster is a good example of more than one of Newton's laws of motion. Explain.






 It's Dynamic! Force and Energy

1.
Gravity is ____.
  The weight of two objects when they are weighed together
  The energy of two objects as they move
  The force of repulsion between two masses
  The force of attraction between two masses
2.
Force only changes the motion of an object or body.
  False
  True
3.
The force or speed of movement is called ____.
  Energy
  Momentum
  Velocity
  Friction
4.
Compare and contrast potential energy with kinetic energy.




5.
Tension is the force that is ____.
  Produced by the energy of two objects
  Produced by the gravitational pull of two objects
  Produced by friction between two objects
  Produced by a stretched object
6.
Explain the Law of Conservation of Energy.




7.
Explain the relationship between free fall and gravity.




8.
Skating in your socks across your living room rug would produce less friction than skating across your kitchen floor in your socks.
  False
  True







Force and Motion


1.
Force and motion are parts of a branch of science called
  Biology
  Physics
  Geology
  Earth science
2.
________ is the measure of gravity's force.
  Weight
  Gravity
  Force
  Speed
3.
________ is the force that pulls everything toward the center of the earth.
  Weight
  Speed
  Gravity
  Force
4.
________ means rate of motion, or how fast something is moving.
  Gravity
  Speed
  Force
  Weight
5.
Climbing a hill is an example of force and motion.
  True
  False
6.
Throwing a Frisbee is an example of force and motion.
  True
  False
7.
Ice-skating is another example of force and motion.
  True
  False
8.
List four more examples of force and motion that are not mentioned in this article.




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