Sunday, December 25, 2011

8th Grade Unit #3 Wave Interactions

 WAVE INTERACTIONS


VSC CONTENT INDICATORS AND OBJECTIVES
5. 6. D. WAVE INTERACTIONS

wave is a disturbance that travels either through a medium (mechanical waves, such as sound waves) or through space (electromagnetic waves, such as light waves).

·       Wave is a disturbance or variation that carries energy progressively from point to point in a medium or space without transporting matter.
·       Mechanical waves move through a medium where the particles collide back and forth in oscillations or vibrations to transfer kinetic energy but the medium itself does not flow with it.
·       




BIG IDEAS

Examples of mechanical waves are waves on a string and sound waves.
·       Electromagnetic wave is a wave of energy consisting of electric and magnetic fields, oscillating at right angles to each other.   These waves disturb electric and magnetic fields instead of particles.  Electromagnetic waves can be transmitted through a vacuum. 
·       Electromagnetic waves form a spectrum of energy from low to high frequency which includes radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, x-rays, and gamma radiation.
·       Wave-particle duality describes the idea that particles can act like waves, and waves can act like particles.   Light is an electromagnetic wave that acts like   waves and particles.
·       Sound is produced when an object vibrates, causing a transfer of kinetic energy through a medium. 
·       In a longitudinal wave the particles of the medium vibrate back and forth in a direction which is parallel  and anti-parallel to the direction of energy transport.
·       In transverse waves, the vibration of the medium is perpendicular to the motion of the wave.
·       Sound can exist as either a longitudinal or transverse wave in solids.  But in liquids and gases, sound can only exist as a longitudinal wave.
·       Examples of transverse waves include seismic S (secondary) waves, a ripple on a pond, and a wave on a string.
·       The transfer of kinetic energy through a medium produces a series of compressions and rarefactions. 
·       Compressions are areas where the surrounding molecules are crowded together in the medium where wave is propagated. 
·       Rarefactions are areas where the molecules are spread out in the medium where wave is propagated.
Sound is vibrations and has the properties or volume, pitch, and quality.




ASSIGNMENT=Please copy these questions into your journal and answer the questions there

PRE TEST- Waves and Rays, Part I

1.
All waves need some material to travel through.
  False
  True
2.
Electromagnetic radiation is:
  Energy that is electric and magnetic
  Energy that is magnetic and solar
  Energy that is created only by the sun
  Energy that is created by atoms and electricity
3.
EM waves have crests, troughs, and wavelengths.
  False
  True
4.
Radio waves:
  Carry the most energy in the EM spectrum.
  Are the longest waves in the EM spectrum.
  Need water to travel through.
  Are the shortest waves in the EM spectrum.
5.
What does frequency mean?
  How many waves or cycles pass a certain point in one minute
  How many waves or cycles exist at one time
  How many waves or cycles pass a certain point in one hour
  How many waves or cycles pass a certain point in one second
6.
A cycle measures:
  The number of waves passing a certain point in one second
  How long the wavelength is
  How much time it takes the wave to travel from its source to Earth
  A single wave from one crest or trough to the next
7.
Another word for cycles per second is:
  Frequency
  EM radiation
  Hertz
  Waves
8.
Which waves have the highest frequencies?
  UV
  Microwaves
  Waves with the lowest energy
  Waves with the highest energy










Waves and Rays, Part I
9.
Radio waves are used for:
  TV broadcasting
  Cell phones
  Pagers
  All of the above
10.
In general, if a wavelength is short:
  It tells us nothing about the energy and frequency.
  The energy and frequency are low.
  The energy and frequency are medium.
  The energy and frequency are high.




ASSIGNMENT=PLEASE WATCH THIS VIDEO BELOW AND TAKE 10-15 NOTES IN YOUR JOURNAL




First Big Assignment=
VOCABULARY WORDS TO LOOK UP AND PUT IN YOUR JOURNAL
Wave
Mechanical wave
Electromagnetic wave
Transverse wave
Surface wave
Longitudinal wave
Crest
Trough
Compression
Rarefaction
Energy
Medium
Vibration
Amplitude
Frequency
Wavelength
Hertz
Reflection
Refraction
Diffraction
Seismic wave
Primary wave
Secondary wave
Light
Sound
Earthquake
Elasticity
Density
Speed
Intensity
Loudness
Decibels
Doppler Effect
Sonar
Sonogram
Echolocation
Noise
Electromagnetic radiation

Waves and Rays, Part I 
By Cindy Grigg
  


1     Have you ever played in the ocean? The waves can push you around. They can pull the sand out from under your feet. As far out as you can see, there are more waves coming at you all the time.
 2     There are other kinds of waves all around you all the time. You can't see most of them, but they can warm you, burn you, and go right through your body. These are the waves of the electromagnetic spectrum.
 3     These waves come from the same kind of electric force that makes your TV work and from the same kind of magnetic force that holds the picture you drew in art class on your kitchen refrigerator with a magnet. When these two forces act together, they make electromagnetic radiation. This is a kind of energy that is both electric and magnetic. This energy travels in waves.



 4     In some ways, these waves and ocean waves are alike. They have tops called crests. They have bottoms called troughs. The distance from one crest to the next is called a wavelength. Wavelengths can also be measured from one trough to the next. Another way electromagnetic (EM) waves are like ocean waves is that they both move energy from one place to another.




 5     The biggest difference between ocean waves and EM waves is that ocean waves move across water. Energy moves through the water. EM waves don't need anything to move through. They can move across the emptiness of outer space. In outer space where there is nothing for the waves to move through, the waves travel at the speed of light. EM waves can also travel through things. They can travel through air inside a room, around the earth, or through food. Some EM waves can even travel inside your body!

ASSIGNMENT=Please copy the graphic organizer into your journal and complete it from the reading above in the journal


 6     Let's learn more about these mysterious waves. When you turn on a radio, you're using part of the EM spectrum. Radio waves have the longest wavelengths of any of the waves in the EM spectrum. Radio waves can be several miles long, or they can be about the length of a one-foot ruler.
 7     When you turn the dial on the radio, you are changing from one radio frequency to another. Frequency means how many waves pass a certain point in one second. If you could see radio waves, you could stand on the street outside your house and count them. Imagine there is a radio tower at the end of your street. The tower sends out radio signals. If you could see the radio waves, you could count how many of them pass a point in front of you in one second. A single wave from one crest to the next (or one trough to the next) is called a cycle. If five thousand waves passed the point in front of you in one second, the radio signal would have a frequency of five thousand cycles per second. You'd have to be able to count pretty fast!



Please explain what Frequency is   in your journal in 2-3 sentences.


Please explain what a "cycle" is   in your journal in 2-3 sentences.

 8     Another name for cycle per second is hertz. It is abbreviated Hz. Radio waves are used to broadcast radio and TV shows and signals for cellular phones, pagers, and beepers. They carry signals here on Earth and through outer space.
 9     There are seven different types of EM. The frequency of the waves makes each type different. Frequency is the number of cycles that pass a given point in one second. The example above (where you counted radio waves from a tower) had a frequency of five thousand cycles per second. Waves in the EM spectrum that have the lowest frequencies have the least amount of energy. Waves with the highest frequencies have the most energy. The first type we learned about is radio waves. The other six types are microwaves, infrared, visible light, ultraviolet, X rays, and gamma rays.

ASSIGNMENT=Please copy the graphic organizer into your journal and complete it from the reading above in the journal


 10     Microwaves are shorter waves than radio waves - shorter than 11.8 inches. The ones used in microwave ovens to cook food are about five inches long. How do microwaves cook food? When you put food into a microwave, the plate stays cool and the food gets hot. Inside food is water. Plates don't have water inside them. When the microwaves hit the food, the water inside the food begins to vibrate from the energy. Microwaves have a frequency of two billion four hundred fifty million waves per second. The water molecules vibrate with that same frequency. When molecules vibrate, they move. The movement releases heat inside the food. The heat cooks the food very quickly.
 11     Two billion four hundred fifty million waves per second is a really big number. Scientists needed a shorter way to say it. A million cycles is a megahertz, abbreviated MHz. A thousand megahertz, or 1000 MHz, is the same as saying one billion cycles per second. The frequency of a microwave can be written as 2450 MHz. Microwaves are also used for communication and TV satellites and for radar. These have shorter waves than those used for microwave ovens. Communications satellite microwaves can be as short as four-hundredths of an inch. When a wavelength is that short, the frequency is high - three hundred billion cycles per second. This can be written as 300 GHz, or 300 gigahertz. "Giga" means one billion.
 12     Infrared waves are the next ones in the band of EM radiation. If you stand in the sunlight, you can feel warmth from the sun's infrared radiation. Your TV remote works on infrared waves. When you push a button on your TV remote, a microchip in the remote starts a vibration. It produces waves in the infrared range. Infrared waves have frequencies of 100 billion to 100 trillion cycles per second. Here's another prefix to learn: "tera" means one trillion. One terahertz (THz) is one trillion hertz or cycles per second. Since the frequencies of infrared beams are so high, the wavelengths are short-from four-hundredths of an inch to only four-hundred thousandths of an inch.
 13     These infrared beams carry codes. Inside the TV set, another microchip identifies each code and sends a signal to raise or lower the volume, change channels, turn the set on or off, record a program, or do whatever you want it to do. Firefighters use infrared cameras to look through smoke and find survivors. They are used in building construction to find heating and cooling system leaks. They are also used in medicine to diagnose cancers and injuries, similar to X-rays.
 14     Radio, microwaves, and infrared are only part of the waves that make up the EM spectrum. Read Waves and Rays, Part II to find out more.
Copyright © 2011 edHelper


ASSIGNMENT= Please click this website about radio waves and explain @ what you see in your journal      http://www.nrao.edu/images/lera/em_anim.gif




ASSIGNMENT=Please copy these questions into your journal and answer the questions there



_
Waves and Rays, Part I
1.
All waves need some material to travel through.
  False
  True
2.
Electromagnetic radiation is:
  Energy that is electric and magnetic
  Energy that is created only by the sun
  Energy that is created by atoms and electricity
  Energy that is magnetic and solar
3.
EM waves have crests, troughs, and wavelengths.
  False
  True
4.
Radio waves:
  Are the shortest waves in the EM spectrum.
  Carry the most energy in the EM spectrum.
  Need water to travel through.
  Are the longest waves in the EM spectrum.
5.
What does frequency mean?
  How many waves or cycles exist at one time
  How many waves or cycles pass a certain point in one second
  How many waves or cycles pass a certain point in one hour
  How many waves or cycles pass a certain point in one minute
6.
A cycle measures:
  How much time it takes the wave to travel from its source to Earth
  How long the wavelength is
  A single wave from one crest or trough to the next
  The number of waves passing a certain point in one second
7.
Another word for cycles per second is:
  Waves
  EM radiation
  Frequency
  Hertz
8.
Which waves have the highest frequencies?
  UV
  Waves with the lowest energy
  Waves with the highest energy
  Microwaves






9.
Radio waves are used for:
  TV broadcasting
  Cell phones
  Pagers
  All of the above
10.
In general, if a wavelength is short:
  It tells us nothing about the energy and frequency.
  The energy and frequency are low.
  The energy and frequency are medium.
  The energy and frequency are high.







Waves and Rays, Part I
ASSIGNMENT=How are EM waves like ocean waves? How are they different? IN YOUR JOURNAL










Waves and Rays, Part I
ASSIGNMENT-Explain how microwaves work to cook food. IN YOUR JOURNAL








ASSIGNMENT=Please copy these questions into your journal and answer the questions there
Waves and Rays, Part I 
By Cindy Grigg
  



broadcast
satellites
Giga


infrared
communication
gigahertz


satellite
communications
wavelengths


phones
lower
lowest


hertz
short-from
electromagnetic


wavelength
megahertz
trillion


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

     Have you ever played in the ocean? The waves can push you around. They can pull the sand out from under your feet. As far out as you can see, there are more waves coming at you all the time.
     There are other kinds of waves all around you all the time. You can't see most of them, but they can warm you, burn you, and go right through your body. These are the waves of the (1)  _______________________   spectrum.
     These waves come from the same kind of electric force that makes your TV work and from the same kind of magnetic force that holds the picture you drew in art class on your kitchen refrigerator with a magnet. When these two forces act together, they make electromagnetic radiation. This is a kind of energy that is both electric and magnetic. This energy travels in waves.
     In some ways, these waves and ocean waves are alike. They have tops called crests. They have bottoms called troughs. The distance from one crest to the next is called a (2)  _______________________  . Wavelengths can also be measured from one trough to the next. Another way electromagnetic (EM) waves are like ocean waves is that they both move energy from one place to another.
     The biggest difference between ocean waves and EM waves is that ocean waves move across water. Energy moves through the water. EM waves don't need anything to move through. They can move across the emptiness of outer space. In outer space where there is nothing for the waves to move through, the waves travel at the speed of light. EM waves can also travel through things. They can travel through air inside a room, around the earth, or through food. Some EM waves can even travel inside your body!
     

     Let's learn more about these mysterious waves. When you turn on a radio, you're using part of the EM spectrum. Radio waves have the longest wavelengths of any of the waves in the EM spectrum. Radio waves can be several miles long, or they can be about the length of a one-foot ruler.
     When you turn the dial on the radio, you are changing from one radio frequency to another. Frequency means how many waves pass a certain point in one second. If you could see radio waves, you could stand on the street outside your house and count them. Imagine there is a radio tower at the end of your street. The tower sends out radio signals. If you could see the radio waves, you could count how many of them pass a point in front of you in one second. A single wave from one crest to the next (or one trough to the next) is called a cycle. If five thousand waves passed the point in front of you in one second, the radio signal would have a frequency of five thousand cycles per second. You'd have to be able to count pretty fast!
     Another name for cycle per second is (3)  _______________________  . It is abbreviated Hz. Radio waves are used to (4)  _______________________   radio and TV shows and signals for cellular (5)  _______________________  , pagers, and beepers. They carry signals here on Earth and through outer space.
     There are seven different types of EM. The frequency of the waves makes each type different. Frequency is the number of cycles that pass a given point in one second. The example above (where you counted radio waves from a tower) had a frequency of five thousand cycles per second. Waves in the EM spectrum that have the(6)  _______________________   frequencies have the least amount of energy. Waves with the highest frequencies have the most energy. The first type we learned about is radio waves. The other six types are microwaves, infrared, visible light, ultraviolet, X rays, and gamma rays.
     Microwaves are shorter waves than radio waves - shorter than 11.8 inches. The ones used in microwave ovens to cook food are about five inches long. How do microwaves cook food? When you put food into a microwave, the plate stays cool and the food gets hot. Inside food is water. Plates don't have water inside them. When the microwaves hit the food, the water inside the food begins to vibrate from the energy. Microwaves have a frequency of two billion four hundred fifty million waves per second. The water molecules vibrate with that same frequency. When molecules vibrate, they move. The movement releases heat inside the food. The heat cooks the food very quickly.
     Two billion four hundred fifty million waves per second is a really big number. Scientists needed a shorter way to say it. A million cycles is a (7)  _______________________  , abbreviated MHz. A thousand megahertz, or 1000 MHz, is the same as saying one billion cycles per second. The frequency of a microwave can be written as 2450 MHz. Microwaves are also used for (8)  _______________________   and TV (9)  _______________________   and for radar. These have shorter waves than those used for microwave ovens.(10)  _______________________   (11)  _______________________   microwaves can be as short as four-hundredths of an inch. When a wavelength is that short, the frequency is high - three hundred billion cycles per second. This can be written as 300 GHz, or 300 (12)  _______________________  . "(13)  _______________________  " means one billion.
     Infrared waves are the next ones in the band of EM radiation. If you stand in the sunlight, you can feel warmth from the sun's infrared radiation. Your TV remote works on(14)  _______________________   waves. When you push a button on your TV remote, a microchip in the remote starts a vibration. It produces waves in the infrared range. Infrared waves have frequencies of 100 billion to 100 trillion cycles per second. Here's another prefix to learn: "tera" means one trillion. One terahertz (THz) is one(15)  _______________________   hertz or cycles per second. Since the frequencies of infrared beams are so high, the (16)  _______________________   are(17)  _______________________   four-hundredths of an inch to only four-hundred thousandths of an inch.

     These infrared beams carry codes. Inside the TV set, another microchip identifies each code and sends a signal to raise or (18)  _______________________   the volume, change channels, turn the set on or off, record a program, or do whatever you want it to do. Firefighters use infrared cameras to look through smoke and find survivors. They are used in building construction to find heating and cooling system leaks. They are also used in medicine to diagnose cancers and injuries, similar to X-rays.

     Radio, microwaves, and infrared are only part of the waves that make up the EM spectrum. Read Waves and Rays, Part II to find out more.

Copyright © 2011 edHelper









ASSIGNMENT=Please copy these questions into your journal and answer the questions there
Circle the correct word.
1.
gigahertz
gigahirtz
gigaherz
gigahert
2.
megahertz
mehguhhurt
megahert
mgahertz
3.
wavelingth
wavelengtth
wavelength
wavelenth
4.
spectrum
spetrum
specrum
spectum
5.
volume
voolume
volyom
valume
6.  
communication
communicetion
cemmenocition
cammunication
7.
outer
uotor
uoter
otur
8.
pagers
pgers
payjur
paggers
9.
myssterious
mystirious
mysteriuos
mysterious
10.
prifix
prefix
preffix
preix
11.
fohz
phenis
phonis
phones
12.
frequecy
frequeny
frequency
freqeucy
13.
satellite
satellie
satuhliet
satelliti
14.
mehguhhurt
megaherz
mehguhhuts
megahertz
15.
Gigaa
Giga
Gigga
Gia
16.
microchip
micrachip
microchep
microochip
17.
celluler
cellular
cillular
sehyuhlur
18.
wurs
wors
works
wuks
19.
terahetz
terahert
terehertz
terahertz
20.
ihnfurehd
infared
infrarred
infrared
21.
Gige
Giga
Gigaa
Gia
22.
ruler
rulor
ralur
roolu
23.
ihlehktrahmagnehtihk
eletromagnetic
electromagnetic
electroagnetic
24.
braodcest
boadcast
braodcast
broadcast

Please click this site and learn about sound waves
click to "the physics of sound"

Please take 10 notes about what you learned from the site




Waves and Rays, Part II 
By Cindy Grigg
  


1     In Waves and Rays, Part I, you learned about radio, microwave, and infrared waves in the electromagnetic (EM) spectrum.
 2     Just above the infrared band of the EM spectrum is the spectrum of visible light. This part of the EM spectrum we CAN see. The waves are between 30 millionths of an inch and 14 millionths of an inch. These have very high frequencies, ranging from a hundred trillion to a thousand trillion cycles per second. Your eyes and the eyes of every creature on Earth have evolved to be able to see these particular light waves.
 3     Light appears to be white to us. But by using a prism, we can separate light into its different colors. The colors are red, orange, yellow, green, blue, indigo, and violet. Each color has its own wavelength and its own frequency. You can remember the order of the colors by remembering Roy G. Biv. Each letter stands for a color in the spectrum. We see these colors in a rainbow in the sky. Sunlight passing through raindrops in the sky is refracted, or bent. When this happens, the light waves slow down. Starting with red, each color that follows has a shorter wavelength and a higher frequency than the one before it. A rainbow can only be seen in the early morning or later afternoon, when the sun is no higher than 42 degrees above the horizon.

ASSIGNMENT=Please copy the graphic organizer into your journal and complete it from the reading above in the journal

 4     All the colors of the visible light spectrum combine in white light to let you see. If there's no light, you can't see color. To see, you must have light from the sun or from an electric light bulb, a fire, or another source. Everything you see has its own color. When light shines on an object, the molecules of the object absorb most of the wavelengths of the visible spectrum. When they don't absorb them, the wavelengths are reflected. If an object reflects only the red wavelengths, the object looks red to you. If the object reflects green, you see the object as green. If an object reflects all colors, you see the object as white. If an object absorbs all colors, you see it as black.

ASSIGNMENT=Please copy the graphic organizer into your journal and complete it from the reading above in the journal


 5     Higher up on the EM spectrum are ultraviolet (UV) waves. These waves have higher frequency, more than one thousand trillion cycles per second, and shorter wavelength. When UV waves hit some materials that "fluoresce," or glow, they produce visible light. Special "black light" fluorescent tubes send out energy in UV wavelengths only a billionth of an inch long. Under black light, certain types of material have an eerie glow. These UV rays are what cause your skin to sunburn. A small amount of UV radiation isn't harmful to you; in fact, it allows your body to produce vitamin D that you need for strong bones. Too much UV will damage your skin. It can cause cancers, wrinkles, and early aging of the skin.



 6     The next band above UV waves is X rays. Notice that the name has changed from "waves" to "rays." From here on up the spectrum, wavelengths grow smaller and frequencies become extremely high. The radiation carries large amounts of energy so they are called rays. X rays have wavelengths around one ten-billionth of an inch or more. Their frequencies are about one million trillion cycles per second. Their energy is so great that just a brief burst of them can kill diseased cells all the way inside your body. Ultraviolet waves damage the skin on the outside of your body, but X rays go much deeper.


ASSIGNMENT=Please copy the graphic organizer into your journal and complete it from the reading above in the journal



Please click this site and learn about light . http://www.gelighting.com/na/home_lighting/gela/students/science.htm
Pinhole cameraWhat is light?Separating light with a prismReflecting lightBending light
click to "these "


Please take 20 notes about what you learned from the site



 7     Doctors use X rays to take pictures inside your body. You may have had an X ray taken of your teeth or of a broken bone. Having an X ray taken of a part of your body every now and then is generally safe. X ray technicians must protect themselves from X rays so that they are not exposed to too much radiation. A lead shield or an apron made of lead will not let X rays penetrate.
 8     The last part of the EM spectrum is the gamma-ray band. Gamma rays are extremely high energy. They have a frequency of around one hundred million trillion cycles per second. Gamma rays are as much as ten billion times more energetic than visible light. These powerful rays are released into Earth's atmosphere when a nuclear bomb explodes and are given off by the radioactive fallout. If a gamma ray passes through a healthy human cell, it can knock electrons from some of the cell's atoms. After enough of this damage, the cell may die. That's why nuclear accidents cause radiation sickness.





What do gamma-rays show us?

If you could see gamma-rays, the night sky would look strange and unfamiliar.The gamma-ray moon just looks like a round blob - lunar features are not visible. In high-energy gamma rays, the Moon is actually brighter than the quiet Sun. This image was taken by EGRET.
Gamma-ray moon



Credit: D.J. Thompson, D.L. Bertsch (NASA/GSFC),
D.J. Morris (UNH), R. Mukherjee (NASA/GSFC/USRA)



 9     Doctors use gamma rays to destroy diseased cells and make patients healthy again. Gamma rays and X rays used in radiation therapy can target the diseased cells of tumors. The tumor cells are destroyed and healthy cells can continue to grow.
 10     Scientists in the last hundred years have found ways to create and use electromagnetic energy. Your everyday life is filled with EM rays that light your sight, cook your food, change channels on your TV, and entertain you. What would we do without them?

ASSIGNMENT=Please copy the graphic organizer into your journal and complete it from the reading above in the journal


 11     Earth's atmosphere blocks many infrared waves, most ultraviolet waves, all X rays, and all gamma rays. There would be no life on Earth if all these high-energy waves and rays were able to get through the atmosphere.
Copyright © 2011 edHelper




ASSIGNMENT=Please copy these questions into your journal and answer the questions there
Waves and Rays, Part II
1.
What is the part of the EM spectrum that we can see?
  Infrared
  Visible light
  X rays
  Gamma rays
2.
At what times of the day can rainbows be seen?
  Early afternoon and late morning
  Early morning and late afternoon
  Sunrise and sunset
  Any time of day
3.
In what order do the colors of the spectrum appear?
  Yellow, green, blue, indigo, violet, orange, and red
  Red, orange, yellow, green, blue, indigo, and violet
  Blue, violet, indigo, green, red, yellow, and orange
  In any order
4.
Ultraviolet (UV) waves can:
  Enable your body to produce Vitamin D
  Cause cancers
  Cause skin damage
  All of the above
5.
X rays can:
  Only pass through your skin
  Help your body make Vitamin D
  Be used to take "pictures" of broken bones
  Both b and c are correct
6.
Nuclear bombs release:
  Infrared waves
  X rays
  UV waves
  Gamma rays












Waves and Rays, Part II
Assignment= Briefly explain the different types of electromagnetic energy.
FULLY EXPLAIN IN YOUR JOURNAL











ASSIGNMENT=Please copy these questions into your journal and answer the questions there



Waves and Rays, Part II 
By Cindy Grigg
  



certain
separate
infrared
wrinkles


billion
radio
radioactive
   atmosphere


fallout
billionth
nuclear
ultraviolet


generally 
gamma-ray
 fluoresce
brief


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

     In Waves and Rays, Part I, you learned about (1)  _______________________  , microwave, and(2)  _______________________   waves in the electromagnetic (EM) spectrum.
     Just above the infrared band of the EM spectrum is the spectrum of visible light. This part of the EM spectrum we CAN see. The waves are between 30 millionths of an inch and 14 millionths of an inch. These have very high frequencies, ranging from a hundred trillion to a thousand trillion cycles per second. Your eyes and the eyes of every creature on Earth have evolved to be able to see these particular light waves.
     Light appears to be white to us. But by using a prism, we can (3)  _______________________   light into its different colors. The colors are red, orange, yellow, green, blue, indigo, and violet. Each color has its own wavelength and its own frequency. You can remember the order of the colors by remembering Roy G. Biv. Each letter stands for a color in the spectrum. We see these colors in a rainbow in the sky. Sunlight passing through raindrops in the sky is refracted, or bent. When this happens, the light waves slow down. Starting with red, each color that follows has a shorter wavelength and a higher frequency than the one before it. A rainbow can only be seen in the early morning or later afternoon, when the sun is no higher than 42 degrees above the horizon.
     All the colors of the visible light spectrum combine in white light to let you see. If there's no light, you can't see color. To see, you must have light from the sun or from an electric light bulb, a fire, or another source. Everything you see has its own color. When light shines on an object, the molecules of the object absorb most of the wavelengths of the visible spectrum. When they don't absorb them, the wavelengths are reflected. If an object reflects only the red wavelengths, the object looks red to you. If the object reflects green, you see the object as green. If an object reflects all colors, you see the object as white. If an object absorbs all colors, you see it as black.



     Higher up on the EM spectrum are ULTRAVIOLET RAYS. These waves have higher frequency, more than one thousand trillion cycles per second, and shorter wavelength. When UV waves hit some materials that "(4)  _______________________  ," or glow, they produce visible light. Special "black light" fluorescent tubes send out energy in UV wavelengths only a (5)  _______________________   of an inch long. Under black light, (6)  _______________________   types of material have an eerie glow. These UV rays are what cause your skin to sunburn. A small amount of UV radiation isn't harmful to you; in fact, it allows your body to produce vitamin D that you need for strong bones. Too much UV will damage your skin. It can cause cancers, (7)  _______________________  , and early aging of the skin.
     The next band above UV waves is X rays. Notice that the name has changed from "waves" to "rays." From here on up the spectrum, wavelengths grow smaller and frequencies become extremely high. The radiation carries large amounts of energy so they are called rays. X rays have wavelengths around one ten-billionth of an inch or more. Their frequencies are about one million trillion cycles per second. Their energy is so great that just a (8)  _______________________   burst of them can kill diseased cells all the way inside your body. Ultraviolet waves damage the skin on the outside of your body, but X rays go much deeper.
     Doctors use X rays to take pictures inside your body. You may have had an X ray taken of your teeth or of a broken bone. Having an X ray taken of a part of your body every now and then is (9)  _______________________   safe. X ray technicians must protect themselves from X rays so that they are not exposed to too much radiation. A lead shield or an apron made of lead will not let X rays penetrate.
     The last part of the EM spectrum is the (10)  _______________________   band. Gamma rays are extremely high energy. They have a frequency of around one hundred million trillion cycles per second. Gamma rays are as much as ten (11)  _______________________   times more energetic than visible light. These powerful rays are released into Earth's(12)  _______________________   when a nuclear bomb explodes and are given off by the (13)  _______________________   (14)  _______________________  . If a gamma ray passes through a healthy human cell, it can knock electrons from some of the cell's atoms. After enough of this damage, the cell may die. That's why(15)  _______________________   accidents cause radiation sickness.
     Doctors use gamma rays to destroy diseased cells and make patients healthy again. Gamma rays and X rays used in radiation therapy can target the diseased cells of tumors. The tumor cells are destroyed and healthy cells can continue to grow.
     Scientists in the last hundred years have found ways to create and use electromagnetic energy. Your everyday life is filled with EM rays that light your sight, cook your food, change channels on your TV, and entertain you. What would we do without them?
     Earth's atmosphere blocks many infrared waves, most (16)  _______________________   waves, all X rays, and all gamma rays. There would be no life on Earth if all these high-energy waves and rays were able to get through the atmosphere.
 

Copyright © 2011 edHelper







Waves and Rays, Part II
ASSIGNMENT=Briefly explain the different types of electromagnetic energy.
FULLY EXPLAIN IN YOUR JOURNAL
















ASSIGNMENT=Please copy these questions into your journal and answer the questions there


Waves and Rays, Part II 
By Cindy Grigg
  



certain
separate
infrared
wrinkles


billion
radio
radioactive
   atmosphere


fallout
billionth
nuclear
ultraviolet


generally 
gamma-ray
 fluoresce
brief


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

     In Waves and Rays, Part I, you learned about (1)  _______________________  , microwave, and(2)  _______________________   waves in the electromagnetic (EM) spectrum.
     Just above the infrared band of the EM spectrum is the spectrum of visible light. This part of the EM spectrum we CAN see. The waves are between 30 millionths of an inch and 14 millionths of an inch. These have very high frequencies, ranging from a hundred trillion to a thousand trillion cycles per second. Your eyes and the eyes of every creature on Earth have evolved to be able to see these particular light waves.
     Light appears to be white to us. But by using a prism, we can (3)  _______________________   light into its different colors. The colors are red, orange, yellow, green, blue, indigo, and violet. Each color has its own wavelength and its own frequency. You can remember the order of the colors by remembering Roy G. Biv. Each letter stands for a color in the spectrum. We see these colors in a rainbow in the sky. Sunlight passing through raindrops in the sky is refracted, or bent. When this happens, the light waves slow down. Starting with red, each color that follows has a shorter wavelength and a higher frequency than the one before it. A rainbow can only be seen in the early morning or later afternoon, when the sun is no higher than 42 degrees above the horizon.
     All the colors of the visible light spectrum combine in white light to let you see. If there's no light, you can't see color. To see, you must have light from the sun or from an electric light bulb, a fire, or another source. Everything you see has its own color. When light shines on an object, the molecules of the object absorb most of the wavelengths of the visible spectrum. When they don't absorb them, the wavelengths are reflected. If an object reflects only the red wavelengths, the object looks red to you. If the object reflects green, you see the object as green. If an object reflects all colors, you see the object as white. If an object absorbs all colors, you see it as black.
     Higher up on the EM spectrum are ULTRAVIOLET RAYS. These waves have higher frequency, more than one thousand trillion cycles per second, and shorter wavelength. When UV waves hit some materials that "(4)  _______________________  ," or glow, they produce visible light. Special "black light" fluorescent tubes send out energy in UV wavelengths only a (5)  _______________________   of an inch long. Under black light, (6)  _______________________   types of material have an eerie glow. These UV rays are what cause your skin to sunburn. A small amount of UV radiation isn't harmful to you; in fact, it allows your body to produce vitamin D that you need for strong bones. Too much UV will damage your skin. It can cause cancers, (7)  _______________________  , and early aging of the skin.
     The next band above UV waves is X rays. Notice that the name has changed from "waves" to "rays." From here on up the spectrum, wavelengths grow smaller and frequencies become extremely high. The radiation carries large amounts of energy so they are called rays. X rays have wavelengths around one ten-billionth of an inch or more. Their frequencies are about one million trillion cycles per second. Their energy is so great that just a (8)  _______________________   burst of them can kill diseased cells all the way inside your body. Ultraviolet waves damage the skin on the outside of your body, but X rays go much deeper.
     Doctors use X rays to take pictures inside your body. You may have had an X ray taken of your teeth or of a broken bone. Having an X ray taken of a part of your body every now and then is (9)  _______________________   safe. X ray technicians must protect themselves from X rays so that they are not exposed to too much radiation. A lead shield or an apron made of lead will not let X rays penetrate.
     The last part of the EM spectrum is the (10)  _______________________   band. Gamma rays are extremely high energy. They have a frequency of around one hundred million trillion cycles per second. Gamma rays are as much as ten (11)  _______________________   times more energetic than visible light. These powerful rays are released into Earth's(12)  _______________________   when a nuclear bomb explodes and are given off by the (13)  _______________________   (14)  _______________________  . If a gamma ray passes through a healthy human cell, it can knock electrons from some of the cell's atoms. After enough of this damage, the cell may die. That's why(15)  _______________________   accidents cause radiation sickness.
     Doctors use gamma rays to destroy diseased cells and make patients healthy again. Gamma rays and X rays used in radiation therapy can target the diseased cells of tumors. The tumor cells are destroyed and healthy cells can continue to grow.
     Scientists in the last hundred years have found ways to create and use electromagnetic energy. Your everyday life is filled with EM rays that light your sight, cook your food, change channels on your TV, and entertain you. What would we do without them?
     Earth's atmosphere blocks many infrared waves, most (16)  _______________________   waves, all X rays, and all gamma rays. There would be no life on Earth if all these high-energy waves and rays were able to get through the atmosphere.
 

Copyright © 2011 edHelper


ASSIGNMENT=PLEASE WATCH THIS VIDEO BELOW AND TAKE 10-15 NOTES IN YOUR JOURNAL






The Nature of Light Back to Top

White light is separated into the different colors (=wavelengths) of light by passing it through a prism. Wavelength is defined as the distance from peak to peak (or trough to trough). The energy of is inversely porportional to the wavelength: longer wavelengths have less energy than do shorter ones.
Wavelength and other saspects of the wave nature of light. Image from Purves et al., Life: The Science of Biology, 4th Edition, by Sinauer Associates (www.sinauer.com) and WH Freeman (www.whfreeman.com), used with permission.
The order of colors is determined by the wavelength of light. Visible light is one small part of the electromagnetic spectrum. The longer the wavelength of visible light, the more red the color. Likewise the shorter wavelengths are towards the violet side of the spectrum. Wavelengths longer than red are referred to as infrared, while those shorter than violet are ultraviolet.
The electromagnetic spectrum. Image from Purves et al., Life: The Science of Biology, 4th Edition, by Sinauer Associates (www.sinauer.com) and WH Freeman (www.whfreeman.com), used with permission.
Light behaves both as a wave and a particle. Wave properties of light include the bending of the wave path when passing from one material (medium) into another (i.e. the prism, rainbows, pencil in a glass-of-water, etc.). The particle properties are demonstrated by the photoelectric effect. Zinc exposed to ultraviolet light becomes positively charged because light energy forces electrons from the zinc. These electrons can create an electrical current. Sodium, potassium and selenium have critical wavelengths in the visible light range. The critical wavelength is the maximum wavelength of light (visible or invisible) that creates a photoelectric effect.

ASSIGNMENT=Please copy these questions into your journal and answer the questions there





POST TEST - Waves and Rays, Part II

1.
What is the part of the EM spectrum that we can see?
  Visible light
  Gamma rays
  X rays
  Infrared
2.
At what times of the day can rainbows be seen?
  Early afternoon and late morning
  Sunrise and sunset
  Any time of day
  Early morning and late afternoon
3.
In what order do the colors of the spectrum appear?
  Yellow, green, blue, indigo, violet, orange, and red
  In any order
  Red, orange, yellow, green, blue, indigo, and violet
  Blue, violet, indigo, green, red, yellow, and orange
4.
Ultraviolet (UV) waves can:
  Enable your body to produce Vitamin D
  Cause cancers
  Cause skin damage
  All of the above
5.
X rays can:
  Only pass through your skin
  Help your body make Vitamin D
  Be used to take "pictures" of broken bones
  Both b and c are correct
6.
Nuclear bombs release:
  Gamma rays
  X rays
  Infrared waves
  UV waves










ASSIGNMENT= In your journal write a paragraph using
all of the words that are given.


1.
  
gamma, billion, gamma-ray, fallout  






2.
  
electromagnetic, visible, produce, atmosphere, bomb  














POST TEST ASSIGNMENT=Please copy these questions into your 
journal and answer the questions there
       What is the difference between mechanical wave and electromagnetic wave?
·       What are the three main types of mechanical waves? Describe each type and give an example of each type.
·       What are the different properties of waves? Describe each property.
·       What is the difference between static electricity and current electricity?
·       What is the difference between reflection and refraction?
·       What causes seismic waves?
·       What are the different types of seismic waves? Describe each type.
·       What is sound?
·       How does sound travel through a medium?
·       What is Doppler Effect? What causes the Doppler Effect?
·       What is light?
·       What are the different types of electromagnetic waves? Describe each type.
·       Compare and contrast electromagnetic waves.

Reflections with Mirrors


Activity that will introduce students to the concept of reflection and the Laws of Reflection.

Making Light of Science

Featuring three lessons and activities that introduce students to the electromagnetic spectrum and the wave nature of light; reflection, absorption, and scattering of light and how the eyes perceive different colors; and the roles of eye and brain in the perception of color.


The Electromagnetic Spectrum: Waves of Energy

This website provides activities that will help students understand that the sun’s energy is transferred to Earth by electromagnetic waves. These activities will likewise deepen students’ understanding about the different types of electromagnetic waves; how they are classified and how each type of wave is used.


What's the Frequency, Roy G. Biv?

The objective of this activity is for the students to discover and verify the relationship between Wavelength and Frequency of the Electromagnetic Spectrum.

Visible Light

In this activity, students will conduct a light absorption experiment, chart their observations during the experiment, and   draw conclusions about how color affects heat absorption.

Finding Monster Waves

Features a lesson and activities that help students to learn the parts of a wave and define wave height, wavelength, and wave period.  They will connect the   concepts to ocean waves, their varying sizes and where to find giant waves. The students will be able to create waves using the National Geographic Wave Simulator.











W
atch t
he video  "Sound Waves"  below and take notes in your journal






















POST TEST - Waves and Rays, Part II

1.
What is the part of the EM spectrum that we can see?
  Visible light
  Gamma rays
  X rays
  Infrared
2.
At what times of the day can rainbows be seen?
  Early afternoon and late morning
  Sunrise and sunset
  Any time of day
  Early morning and late afternoon
3.
In what order do the colors of the spectrum appear?
  Yellow, green, blue, indigo, violet, orange, and red
  In any order
  Red, orange, yellow, green, blue, indigo, and violet
  Blue, violet, indigo, green, red, yellow, and orange
4.
Ultraviolet (UV) waves can:
  Enable your body to produce Vitamin D
  Cause cancers
  Cause skin damage
  All of the above
5.
X rays can:
  Only pass through your skin
  Help your body make Vitamin D
  Be used to take "pictures" of broken bones
  Both b and c are correct
6.
Nuclear bombs release:
  Gamma rays
  X rays
  Infrared waves
  UV waves









Name _____________________________

Date ___________________
(Key 1 - Answer ID # 0435713)
Write a paragraph using all of the words that are given.

1.
  
gamma, billion, gamma-ray, fallout  










2.
  
electromagnetic, visible, produce, atmosphere, bomb  














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