# Second Semester Review

Waves, Sound, Light, Electricity, Special Relativity

1. The time it takes for a vibration to repeat is called its ___.

 A. frequency B. wavelength C. period D. amplitude

Wavelength and Amplitude

Frequency and Period

2. A mass is hanging at the end of a string and caused to vibrate back and forth as pendulum. The time it takes to vibrate back and forth depends on its ___.

 A. mass B. amplitude C. composition D. length

Use the above diagram to respond to questions #3-#7.

3. Which letter represents the amplitude of a wave?

4. Which letter represents the wavelength of a wave?

5. Which letter represents the maximum displacement a particle experiences during any portion of its vibration?

6. Which letter represents the total distance a wave will travel during a period?

Amplitude (#3 and #5)

Wavelength (#4 and #6)

7. Which type of wave is represented by the diagram?

 A. transverse B. longitudinal C. sound D. surface

Categories of waves

8. Which of the following units is used to state frequency?

 A. seconds B. meters C. newtons D. hertz

Frequency

9. If you wished to find the speed of a wave, you could accomplish this by measuring its:

 A. amplitude and period B. wavelength and period C. wavelength and amplitude D. frequency and amplitude

v = f * lambda

Frequency-Period Relationship

10. A wave passes from a slow medium into one in which it moves fast. Which of the following must increase?

 A. period B. frequency C. wavelength D. amplitude

Wave speed

11. The speed of a sound wave in air depends most on ____.

 A. wavelength B. amplitude C. frequency D. temperature

Wave speed and the Speed of Sound

12. Which of the following is not a cause of standing waves?

 A. interference B. resonance C. reflection D. refraction

What is a Standing Wave

13. In a standing wave, the region that vibrates very little or not at all is called ___.

 A. a node B. an antinode C. the Doppler region

Nodes and Antinodes

14. In a standing wave the distance between successive antinodes represents ____ wavelength(s).

 A. 2 B. 1 C. 1/2 D. 1/3

Nodes and Antinodes

15. The driver of a car that is moving toward you sounds the car's horn. As a result, the frequency of the horn that you hear is ____ that heard by the driver.

 A. higher than B. lower than C. the same as

The Doppler Effect

16. This phenomenon (in #15) is known as ___.

 A. refraction B. reflection C. resonance D. the Doppler effect

The Doppler Effect and Shock Waves

17. If the car (in #15) could move faster than the speed of sound, a ____ would be created.

 A. shock wave B. surface C. transverse D. standing wave

Shock Waves

18. As a supersonic aircraft passes, a high-amplitude wave trails behind it as shown. Which diagram best represents the wave created by the fastest aircraft?

Shock Waves

19. Sound travels by means of a ___ wave.

 A. transverse B. longitudinal C. surface D. token

Sound is a Longitudinal Wave

20. The pitch of a sound wave detected by human ears is determined by the wave's ___ .

 A. speed B. amplitude C. frequency D. loudness

Pitch and Frequency

21. The loudness of a sound wave detected by human ears is mostly determined by the wave's:

 A. speed. B. amplitude. C. frequency. D. velocity.

Intensity and the Decibel Scale

22. Why can't sound waves travel through outer space (Why can't we hear the sun)?

1. Nothing vibrates in space.
2. Sound waves require a medium.
3. Sound waves do travel through space; we aren't sensitive to their frequencies.
4. Sound waves do travel through space; we choose not to listen to them.

Sound as a Mechanical Wave

23. Resonance is created when:

1. an object is forced to vibrate at its natural frequency.
2. an object is forced to vibrate at any old frequency.
3. a grape is dried and then covered with milk chocolate.

Resonance

24. The lowest frequency at which an open tube will resonate is known as the ___.

 A. 4th harmonic B. 3rd harmonic C. 2nd harmonic D. fundamental

Fundamental Frequency and Harmonics

25. Two organ pipes of equal length are played at their lowest resonating frequencies. Pipe "A" is open at both ends while "B" is closed at one end and open at the other. Which of the following will occur?

1. The frequency of "A" will be twice that of "B".
2. The frequency of "B" will be twice that of "A ä".
3. The frequency of "B" will be three times that of "A".
4. Both pipes will sound the same frequency.

Open-End Air Columns

Closed-End Air Columns

26. Two tuning forks are struck and an oscillating tone that alternates between loud and soft twice a second is heard. This phenomenon is known as ___.

 A. a shock wave B. a sonic boom C. a bow wave D. beats

Interference and Beats

27. The phenomenon in # 26 is a result of ___.

 A. the Doppler effect B. interference C. resonance

Interference and Beats

28. If one of the tuning forks in #26 has a frequency of 220 Hz, which of the following is a possible frequency of the other fork?

 A. 440 Hz B. 110 Hz C. 880 Hz D. 222 Hz

Interference and Beats

29. Which of the following is the best approximation of the speed of light in a vacuum?

 A. 300,000 m/s B. 300,000 km/s C. 300 m/s D. 300 km/s

Optical Density and Light Speed

30. When light enters into a piece of glass from air, its speed ___.

 A. increases B. decreases C. stays the same

Optical Density and Light Speed

31. Which of the following is not a type of electromagnetic radiation?

 A. sound B. gamma C. infrared D. ultraviolet E. X-ray

Electromagnetic Spectrum

32. What is a light year?

1. the time it takes for light to travel across the solar system.
2. the distance light travels in one year.
3. 365 days of low-fat food consumption.
4. a year in which there is very little homework assigned.

33. One polarizing filter is placed over another and no light is transmitted. Through what angle must one filter be rotated in order for maximum transmission to occur?

 A. 30 deg. B. 45 deg. C. 90 deg. D. 180 deg. E. 360 deg.

Polarization

34. The fact that light can be polarized is evidence that it travels in the form of a ___ wave.

 A. transverse B. longitudinal C. surface

Polarization

35. Which of the following situations would most likely cause light to become polarized.

1. Light is transmitted through a windshield.
2. Light is reflected off of the surface of a windshield at a low angle.
3. Light is emitted by a light bulb.
4. Light is reflected off of a piece of paper.

Polarization

36. The colors that we see are a result of our response to the ___ of visible light.

 A. frequency B. amplitude C. speed

Visible Light Spectrum

37. This color is interpreted when we see the longest wavelength of visible light.

Visible Light Spectrum

38. Red + green = ____.

39. White - yellow = ____.

Color Subtraction

40. A green apple illuminated by yellow light would appear ____.

Color Subtraction

Object "A" appears red when illuminated by magenta light while "B" appears blue. When illuminated by green light, "A" appears green while "B" appears black.

41. What color would "A" appear in white light?

42. What color would "B" appear in white light?

43. What color would "A" appear in cyan light?

Color Subtraction

44. An artist paints a picture that he wishes to appear the appropriate colors when viewed using the phenomenon of retinal fatigue. What color should the artist paint a red barn?

Color Subtraction

45. Which color is scattered the most by the earth's atmosphere?

46. Which light ray in the diagram above best demonstrates the law of reflection?

The Law of Reflection

47. A plane mirror forms ___ images of most objects because the light rays that reflect off of it are:

 A. real, diverging B. real, converging C. virtual, diverging D. virtual, converging

Real vs. virtual images

48. A light ray passes from substance "A" into "B" then "C" as shown. In which substance does the light ray travel fastest?

Direction of bending (FST and SFA)

49. Light bends as it passes into a new medium because it changes ____.

 A. frequency B. speed C. amplitude D. period

Cause of Refraction

50. The index of refraction of a substance is related to the ___ of light in that substance.

 A. frequency B. speed C. amplitude D. period

Optical density, index of refraction (n), and light speed

51. The index of refraction of light in air has a value of ____.

 A. 0.00 B. 0.50 C. 1.00 D. 1.50 E. 2.00

Consider the diagram at the right for questions #52 -#54.

52. A light ray passes from substance "A" into "B" then "C" at boundaries "X" and "Y" as shown in the diagram at the right. Which substance has the highest index of refraction?

Direction of bending (FST and SFA)

Optical density, index of refraction (n), and light speed

53. Total internal reflection could occur when a light ray meets the ___ boundary from the ___ side?

 A. X ; A B. X ; B C. Y ; C

Two conditions for TIR

54. Imagine "A", "B","C" represented the substances air, glass, diamond. Which is the most likely match?

1. A : air; B : glass; C : diamond
2. A : air; B : diamond; C : glass
3. A : glass; B : air; C : diamond
4. A : glass; B : diamond; C : air

Direction of bending (FST and SFA)

Optical density, index of refraction (n), and light speed

55. White light passes through a triangular prism as shown. Which ray most likely represents violet light?

56. Which ray traveled the fastest in the prism?

Two lenses are shown at right. Which of the lenses, A or B or both:

57. is bi-convex?

58. forms virtual images?

59. forms real images?

60. forms reduced images only?

61. can be used as a magnifying lens?

62. can be used to correct near-sightedness?

Converging vs. Diverging Lenses (#57)

63. If an object is placed at a distance from a converging lens that is twice focal length of the lens (at 2F), where will the image be formed?

 A. beyond 2F B. at 2F C. between 2F and F D. between 2F and the lens

Object-Image Relations for Converging Lenses (#58 - 61)

64. If an object is placed at a distance from a converging lens that is between 2f and F, where will the image be formed?

 A. beyond 2F B. at 2F C. between 2F and F D. between 2F and the lens

Object-Image Relations for Converging Lenses (#58 - 61)

65. In which situation above will the image be magnified (larger than the object)?

 A. #63 B. #64 C. #63 and #64 D. neither #63 nor #64

Object-Image Relations for Converging Lenses (#58 - 61)

66. Which of the following is true?

1. Both of the images in #63 and #64 will be real.
2. Both of the images in #63 and #64 will be virtual
3. One of the images in #63 and #64 will be real and the other will be virtual
4. It is impossible to determine the types of images that will be formed in #63 and #64.

Object-Image Relations for Converging Lenses (#58 - 61)

67. A neutral object would acquire a negative charge if it ____.

 A. gained some atoms. B. gained some electrons C. gained some protons D. lost some electrons E. lost some neutrons

68. A neutral balloon is suspended from a string. A charged plastic golf tube is brought nearby. As a result, the balloon will be ____.

1. attracted to the tube
2. repelled by the tube.
3. neither attracted to or repelled by the tube.
4. either attracted or repelled, depending on whether the tube is + or - charged.

69. A plastic tube is charged by rubbing it with fur. The plastic tube acquires a negative charge. This is evidence that ____.

1. plastic molecules have a greater attraction for electrons than fur molecules
2. fur molecules have a greater attraction for electrons than plastic molecules
3. plastic is an insulator and fur is a conductor
4. fur is an insulator and plastic is a conductor

70. In # 69, the tube became charged by _____.

 A. friction B. conduction C. induction D. grounding

A negatively-charged balloon is brought next to two conducting cans that are touching each other as shown above (before). The balloon is closer to can #1 than it is to # 2. While the balloon is near, the cans are separated and the balloon is removed (after).

71. After the balloon is removed, can # 1 is _______.

 A. positively-charged B. negatively-charged C. neutral

72. The process described above is called _______.

 A. charging by friction B. charging by conduction C. charging by induction D. grounding

Charging by Induction

73. Two spheres, made out of the same material are charged as shown in diagram 12. Sphere X is larger than Y. What will happen when the spheres are connected by a wire?

 A. Electrons will flow from X to Y. B. Protons will flow from X to Y. C. Electrons will flow from Y to X. D. Protons will flow from Y to X.

74. Charges will continue to flow (in diagram 12) until ____.

1. the charge on X is the same as the charge on Y.
2. the total amount of potential energy of the charges on X is the same as that on Y.
3. Y has a larger number of excess charges than X.
4. the charges on X are at the same electric potential as those on Y.

75. The resistors in circuit ____ are connected in series.

76. What is the effective/equivalent resistance of circuit "A"?

 A. 1/3 Ohm B. 1 Ohm C. 3 Ohm D. 9 Ohm E. 27 Ohm AB. 81 Ohm

77. What is the effective/equivalent resistance of circuit "B"?

 A. 1/3 Ohm B. 1 Ohm C. 3 Ohm D. 9 Ohm E. 27 Ohm AB. 81 Ohm

78. In order to have the same effective / equivalent resistance in circuit "B" as in "A", each resistor in "B" would have to have a value of ___.

 A. 1/3 Ohm B. 1 Ohm C. 3 Ohm D. 9 Ohm E. 27 Ohm AB. 81 Ohm AC. 243 W

79. What is the current through each resistor in circuit "A"?

 A. 1/3 Amp B. 1 Amp C. 3 Amp D. 6 Amp E. 9 Amp AB. 27 Amp AC. 81 Amp

80. What is the current through each resistor in circuit "B"?

 A. 1/3 Amp B. 1 Amp C. 3 Amp D. 6 Amp E. 9 Amp AB. 27 Amp AC. 81 Amp

81. What is the voltage drop across each resistor in circuit "A"?

 A. 81 V B. 27 V C. 9 V D. 3 V E. 1 V AB. 1/3 V

82. What is the voltage drop across each resistor in circuit "B"?

 A. 81 V B. 27 V C. 9 V D. 3 V E. 1 V AB. 1/3 V

83. At what rate is energy dissipated in circuit "B"?

 A. 1/3 W B. 1 W C. 3 W D. 9 W E. 27 W AB. 81 W AC. 243 W

84. A woman standing on the ground sees a rocket ship move past her at 95% the speed of light. compared to when the rocket is at rest, the woman measures the rocket's length as:

 A. longer. B. shorter. C. the same length.

Length Contraction

85. When an object is pushed to relativistic speeds, its mass is _____.

 A. greater than at rest. B. smaller than at rest. C. the same as at rest.

Relativistic Mass

86. An astronaut traveling at 0.87c holds a 1-meter stick in her hand, moving forward in spear-like fashion. The astronaut sees the spear's length as _____.

 A. 0.5 m B. 0.87 m C. 1 m D. 1.25 m E. 1.5 m

Length Contraction

87. A spaceship that is traveling very fast with respect to your frame of reference, fires a light beam that travels at speed c with respect to the spaceship. You measure the light beam's speed to be _____.

 A. less than c B. more than c C. equal to c

Speed of light

88. According to the special theory of relativity, if you measure your own pulse while traveling at very high speeds, you would notice your pulse rate to ____.

 A. increase B. decrease C. be the same as

Laws of physics are equally valid in all reference frames