Section 22-2 : The Electromagnetic Spectrum Reading Guide pages 636-643
Characteristics of EM Waves: Circle the letter of the best answer for each question.
1. At what speed do EM waves travel in a vacuum?
a. 3,000,000 km/s b. 3,000,000 km/min c. 300,000 km/s d. 300,000 km/min
2. What is the way to find the speed of a wave?
a. Divide wavelength by frequency.c. Divide frequency by wavelength.
b. Multiply wavelength by frequency. d. Add frequency and wavelength
3. What is the entire range of EM waves called?
a. a rainbow b. visible light c. electricity d. the electromagnetic spectrum
4. How are electromagnetic waves arranged?
a. by speed b. by amplitude c. by wavelength or frequency d. by usefulness
Directions: Read the words in the box. Read the sentences. Fill in each blank with the word or phrase that best completes the sentence.
gamma rays / infrared waves / ultraviolet waves / X rays5.EM name means “below red” are ______
.6.EM waves that are produced by some nuclear reactions are ______
7.EM waves discovered in 1895 are ______
8.EM waves whose name means “beyond violet” are ______
Radio Waves
9. Which EM waves have some of the longest wavelengths and lowest frequencies?
- microwaves b. radio waves c. sound waves d. broadcasting waves
Broadcasting Radio Signals 10. Radio waves can transmit information by varying the waves
a. amplitude b. frequency c. pitch d. both a and b
Comparing AM and FM Radio Waves 11. Which affects FM radio waves less than AM radio waves?
a. electrical noise b. temperature c. sunlight d. pressure
Radio Waves and Television
12.Which of EM waves are used to send television signals?
a. microwaves b. radio waves c.sound waves d. broadcasting waves
Microwaves
13.Which of the following is NOT part of the process used to cook food with microwaves?
a. a device called a magnetron produces microwaves
b. The energy of the microwaves penetrates the food and causes water molecules in the food to rotate
c. The rotation of the water molecules causes the temperature of the food to increase.
d The rotation of the water molecules causes the temperature of the food to decrease
Microwaves and Communication
14.Which EM waves are used by cellular phones?
a. radio waves b. microwaves c. gamma rays d. satellite waves
Radar
15.What can a police officer use radar to check?
a. the speed and location of objects c. the weight of objects
b. the size of objects ` d. the color of objects
INFRAred Waves
16.Which gives off infrared waves?
a. only things on Earth b. only the sun c. only buildings and trees d. almost all things
17.The amount of infrared waves an object gives off depends on what?
a. the wave’s speed c.the object’s weight
b.the wave’s color d. the object’s temperature
Visible Light
18.What is the range of wavelengths and frequencies that humans can see?
a. infrared waves c. ultraviolet light
b. visible light d. . X rays
Visible Light from the Sun
19.What is the visible light of all wavelengths combined?
a. white light b. infrared waves c.ultraviolet light d. X rays
Colors of Light
20.What does ROY G. BiV stand for?
a. the last letter of each color of visible lightc. the first letter of each type of EM wave
b. the first letter of each color of visible lightd. the person who discovered visible light
Directions: Read the description. Then, draw a line from the dot next to each description to the matching word.
_____21. Color of the longest wavelength of visible lightA). violet light
_____22. Color of the shortest wavelength of visible lightB). visible spectrum
_____23. The range of colorsC). red light
ULTRA VILOET LIGHT: BAD EFFECTS
24. Which EM waves can cause sunburn, skin cancer, and wrinkles?
a. visible light waves b.infrared waves c. ultraviolet wavesd. X rays
Good Effects
25. Which EM waves can kill bacteria on food and surgical tools?
a. visible light waves b. infrared waves c. ultraviolet waves d. radio waves
26. What do skin cells produce when exposed to a little ultraviolet light?
a. vitamin D b. freckles c. calcium d. vitamin C
X Rays
27. Which EM waves are used to see inside suitcases without opening them?
a. microwaves b. infrared waves c. gamma rays d. X rays
28. Why are X rays useful in the medical field?
a. X rays are stopped by most materials. c. X rays are invisible.
b. X rays can pass through many materials. d. X rays have long wavelengths.
29. What can too much exposure to X rays do?
a. cause sunburn c. overcook food
b. ruin a lead apron d. damage or kill living cells
30. What material can X rays NOT pass through?
a. skin b. lead c. muscles d.clothing
Gamma Rays 31. How do doctors use gamma rays?
a. to take X rays b. to kill cancer cells c.to take temperatures d. to do surgery
32. What is a bad effect of using gamma rays to treat cancer?
a. The tumors may get larger. c. Healthy cells may be killed.
b. The skin may get a sunburn. d. Unhealthy cells may be killed.
33. Gamma rays kill what in food?
a.harmful bacteria b. calories c. taste d. color