Chapter 17 Practice Questions KEY
1. Long wavelength Medium wavelength Short wavelength
1. Long wavelength Radio, Microwave Medium wavelength Infrared, Visible, Ultraviolet Short wavelength X ray, gamma ray
2. What two properties waves are used to attach information to radio signals?
2. What two properties waves are used to attach information to radio signals? Frequency and amplitude
3. Give a specific example of how each of the below EM waves might be used Infrared Gamma Ray
3. Give a specific example of how each of the below EM waves might be used Infrared Night vision, thermal imaging, viper snakes finding prey Gamma Ray Radiation therapy for brain cancer, explosions on the sun
3. Give a specific example of how each of the below EM waves might be used Ultraviolet Microwave
3. Give a specific example of how each of the below EM waves might be used Ultraviolet Insects seeing flowers, sunlight, sunburns, tanning beds Microwave Microwave oven, Radar to detect vehicles, cell phones
3. Give a specific example of how each of the below EM waves might be used Radio
3. Give a specific example of how each of the below EM waves might be used Radio Broadcast television, Radio Stations, Cell Phones
4.What are two main sources of EM waves on earth?
4.What are two main sources of EM waves on earth? The sun and human technology
5. Many different things can occur when an EM wave encounters a medium. List 2 of them
5. Many different things can occur when an EM wave encounters a medium. List 2 of them Reflection, refraction, diffraction, absorption
6. What would happen to an EM wave that never encountered matter?
6. What would happen to an EM wave that never encountered matter? It would continue to travel indefinitely without losing energy
7. What is radiation?
7. What is radiation? Energy that moves as an electromagnetic wave
8.List each of the 7 EM waves in the proper category High frequency Medium frequency Low frequency
8.List each of the 7 EM waves in the proper category HIgh frequency Medium frequency X Ray, Gamma Ray Infrared, visible, ultraviolet Low frequency Radio, Microwave
9.List each of the 7 EM waves in the proper category Low energy Medium energy High energy
9.List each of the 7 EM waves in the proper category Low energy Medium energy High energy Radio, Microwave Infrared, Visible, Ultraviolet X Ray, Gamma Ray
10. Why is UV light dangerous to humans while infrared light is not?
10. Why is UV light dangerous to humans while infrared light is not? UV light has higher energy due to its shorter wavelengths and high frequency. The high energy can be damaging to human cells
11. Label the various ways light can interact with a medium.
11. Label the various ways light can interact with a medium.
11. Label the various ways light can interact with a medium.
11. Label the various ways light can interact with a medium.
12. What is the difference between translucent and opaque materials?
12. What is the difference between translucent and opaque materials? Translucent allows some light through but opaque does not allow any light through
13. Higher energy EM waves penetrate farthest into a dense medium. What colors are more likely to penetrate to the bottom of a lake?
13. Higher energy EM waves penetrate farthest into a dense medium. What colors are more likely to penetrate to the bottom of a lake? Green, blue, indigo, and violet
14. The color of an object depends on what two things?
14. The color of an object depends on what two things? The wavelengths that are available, the wavelengths that are reflected or absorbed
15. What colors of light can the human eyeball detect?
15. What colors of light can the human eyeball detect? Red, green, blue
16. A theater director wants to make the backdrop onstage appear cyan. What colors of light should they shine onto the backdrop?
16. A theater director wants to make the backdrop onstage appear cyan. What colors of light should they shine onto the backdrop? Blue Light and Green Light
17. What colors of pigment would be mixed to create red ink?
17. What colors of pigment would be mixed to create red ink? Yellow and magenta
18. Someone tells you that wearing black on a hot summer day will make you warmer. What could be a possible scientific explanation for this?
18. Someone tells you that wearing black on a hot summer day will make you warmer. What could be a possible scientific explanation for this? Materials that are black absorb all wavelengths of light. That light energy is usually transformed into thermal energy
19. Plants must absorb light in order to produce the chemical energy they use to survive. You have a plant in your house and you want to help it grow. Which color of light should you place your plant under if your options are Red Light, Green Light, or Blue Light?
19. Plants must absorb light in order to produce the chemical energy they use to survive. You have a plant in your house and you want to help it grow. Which color of light should you place your plant under if your options are Red Light, Green Light, or Blue Light? Red or Blue Light. Green Light would likely kill the plant! It would not be able to absorb any light
20. Explain how a prism works?
20. Explain how a prism works? Prisms use refraction to spread out the different wavelengths of light. Each wavelength bends at a slightly different angle
21. How fast do EM waves travel in a vacuum or outer space?
21. How fast do EM waves travel? In outer space/vacuum: a constant speed of approximately 186,000 miles per second On Earth: speed varies depending on what medium the EM wave interacts with
22. What are 2 examples of radiation?
22. What are 2 examples of radiation? Any of the 7 EM waves can be considered radiation
23. Reflection Refraction Absorption Scattering Bending of a wave as it encounters new medium Energy transferred to a medium Waves spread out as some are reflected & some are absorbed Wave bounces off a medium
23. Reflection Refraction Absorption Scattering Bending of a wave as it encounters new medium Energy transferred to a medium Waves spread out as some are reflected & some are absorbed Wave bounces off a medium
24. Give an example of an object/material that is a.opaque: b.translucent: c.transparent:
24. Give an example of an object/material that is a.opaque: (example can be any material that lets no light through) b.translucent: (example can be any material that lets some light through) c.transparent: (example can be any material that lets all/most light through)
25 Which visible light color has a.the highest frequency b.the shortest wavelength - c.the longest wavelengthd.the lowest frequency-
25 Which visible light color has a.the highest frequency Violet b.the shortest wavelength - Violet c.the longest wavelength- Red d.the lowest frequency- Red
26. What are the primary colors of light?
26. What are the primary colors of light? Red, Green, Blue
27. What are the primary colors of pigment?
27. What are the primary colors of pigment? Cyan, Magenta, Yellow