# Unit3 Test

5.  An electric motor accomplishes what task?

 [removed] converts chemical energy into mechanical energy [removed] converts electrical energy into electromagnetic energy [removed] converts electrical energy into mechanical energy [removed] converts mechanical energy into chemical energy [removed] converts mechanical energy into electrical energy

The next five questions refer to these electric meters:

15.  How much electricity was used during the month of June?

 [removed] 2813 kwh [removed] 2582 kwh [removed] 3011 kwh [removed] 2903 kwh [removed] 2744 kwh

17.

How much would this energy cost the consumer? (assume the average rate of \$0.07 per kwh)

 [removed] \$203.00 [removed] \$210.77 [removed] \$196.91 [removed] \$188.90 [removed] \$176.43

18.  What was the meter reading on June 1?

 [removed] 59,301 [removed] 58,300 [removed] 58,410 [removed] 69,411 [removed] 58,310

19.  What was the meter reading on July 1?

 [removed] 61,134 [removed] 61,132 [removed] 61,234 [removed] 61,123 [removed] 61,223

20.  A piece of iron can be made into a permanent magnet by stroking it with a strong magnet.

 [removed] true [removed] false
10.  If the frequency of a wave is 5 Hz, how many waves will pass by a stationary object in 1 minute?

 [removed] 1/5 [removed] 5 [removed] 300 [removed] 60 [removed] 1/300

11.  A submarine captain wishes to know how far away an undersea cliff face is, so he sends out a SONAR signal. After 0.80 seconds, he receives the echo. How far away is the cliff face?

 [removed] 1500 m [removed] 1200 m [removed] 600 m [removed] 3000 m [removed] 2400 m

 Use this figure to answer the next 3 questions:
12.  On the diagram, which letter represents the amplitude?

 [removed] A [removed] B [removed] C [removed] D [removed] E

13.  Which of the letters represents the wavelength?

 [removed] A [removed] B [removed] C [removed] D [removed] E

14.  Which position represents the trough?

 [removed] A [removed] B [removed] C [removed] D [removed] E

1.  If a star is moving away from Earth at a high speed, which of the following would astronomers observe?

 [removed] The star’s spectrum would not be shifted at all. [removed] The star’s spectrum would be shifted towards red. [removed] The star’s spectrum would be shifted towards blue. [removed] There is not enough information given to determine.
5.  The visible spectrum is made of what types of light?

 [removed] red, orange, yellow, green, blue, violet [removed] infrared, red, orange, green, blue, ultraviolet [removed] red, orange, yellow, green, blue, ultraviolet [removed] radio, infrared, colored light, ultraviolet, x-rays, gamma rays
10.  Which of the following has the most energy?

 [removed] x-rays [removed] ultraviolet [removed] visible light [removed] gamma rays [removed] infrared

11.  Which of the following best describes the dual nature of light?

 [removed] Light can be thought of as visible colors or as invisible colors. [removed] Light can be thought of as being white light or a combination of colored light. [removed] Light can be thought of as a mixture of colored light or a mixture of pigments. [removed] Light can be thought of as behaving like a particle or like a wave.

 [removed] It helps them predict solar and lunar eclipses. [removed] It helps them determine what elements make up stars. [removed] It helps them determine the age of the universe. [removed] It helps them know what the planets are made of.
15.  Which of the following has the longest wavelength?

 [removed] infrared [removed] visible light [removed] gamma rays [removed] x-rays [removed] ultraviolet

16.  Which of the following scientists did not attempt to calculate the speed of light?

 [removed] Michelson [removed] Huygens [removed] Galileo [removed] Einstein

17.  Which of the following characteristics of an object would allow no light to pass through?

 [removed] horizontal polarization [removed] opaqueness [removed] transparency [removed] translucency [removed] transmutaticity
19.  The “speed of light” (c) refers to the speed of all electromagnetic waves under what conditions?

 [removed] through the interstellar ether [removed] through a clear liquid, like water [removed] through a perfect vacuum [removed] through the earth’s atmosphere [removed] The speed of light is the same under any conditions.