1. Cutnell/Johnson Physics 8th edition Reading Quiz Questions
Classroom Response System Questions
Chapter 17 The Principle of Linear Superposition and Interference Phenomena
Reading Quiz Questions

2. When two or more waves are present simultaneously at the same place, the resultant disturbance is the sum of the disturbances from the individual waves. What principle or law makes this statement?
a) Principle of Phase Construction
b) Principle of Linear Superposition
c) Law of Cosines
d) Huygens’ Principle
e) Law of Overlapping Waves

3. 17.1.2. Complete the following sentence: The Principle of Linear Superposition may
a) not be applied to longitudinal waves.
b) not be applied to transverse waves.
c) not be applied to electromagnetic waves.
d) be applied to all types waves.
e) be applied only when a wave reflects from a surface.

4. According to the Principle of Superposition, how are two waves combined to produce a resultant wave?
a) The velocity vectors are added together.
b) The amplitudes of the two waves are added algebraically.
c) The amplitudes of the two waves are multiplied together.
d) Waves are always independent of each other and cannot be combined.

5. 17.2.1. Complete the following sentence: Destructive interference occurs when
a) two or more waves are present at the same place and the waves are exactly in phase.
b) two or more sound waves are present at the same place.
c) two or more waves are present at the same place and the resultant disturbance has zero amplitude.
d) two or more waves are present at the same place and a condensation meets a condensation.
e) two or more waves are present at the same place and a rarefaction meets a rarefaction.

6. 17. 2. 2. Wave A has an amplitude of 0
Wave A has an amplitude of 0.5 m and wave B has an amplitude of 0.6 m. When waves A and B travel toward each other, the observed wave amplitude at a certain location and particular time is 0.9 m. Which of the following statements concerning this observation is true?
a) This was an observation in error, since the superposition of these two waves cannot result in an amplitude larger than 0.6 m.
b) This was an observation in error, since the superposition of two these two waves will always result in an amplitude of 1.1 m.
c) This is an example of the superposition of two waves resulting in exactly in phase interference.
d) This is an example of the superposition of two waves resulting in destructive interference.
e) This is an example of the superposition of two waves resulting in constructive interference.

7. The drawing shows two sets of sound waves, created by two sources labeled "A" and "B." The black half-circles represent wave crests from A, and the grey half-circles represent wave crests from B. Suppose that individual wave crests from either source A or source B alone are at +5 µm relative to the undisturbed air molecule positions. What is the displacement of the air molecules at the point marked "x" that is at the mid-point between two crests on each wave?
a) +10 µm
b) +5 µm
c) 0
d) 5 µm
e) 10 µm

8. 17.3.1. Which of the following types of waves exhibit diffraction?
a) only transverse waves
b) only longitudinal waves
c) all waves, except electromagnetic waves
d) all types of waves

9. 17. 3. 2. Consider the situation shown in the drawing
Consider the situation shown in the drawing. Wave fronts of water waves approaching an aperture from the left are shown. Which of the following statements concerning this situation is true?
a) Because the wavelength is much smaller than the
aperture, low dispersion occurs.
b) The wave fronts exiting the aperture should be drawn as
semi-circles.
c) The wave fronts exiting the aperture should be drawn
further apart than those entering the aperture.
d) The amplitudes of the wave fronts will vary, alternating
maxima and minima, with distance away from the aperture.
e) Because the wavelength is much smaller than the aperture, high dispersion occurs.

10. 17. 4. 1. Speaker A is located immediately to the left of speaker B
Speaker A is located immediately to the left of speaker B. Speaker A is emitting sound waves with a frequency of 436 Hz and speaker B is emitting sound waves with the same amplitude as A, but with a frequency of 440 Hz. What would an observer standing directly in front of these speakers hear?
a) The observer’s left ear would hear a lower frequency than the observer’s right ear.
b) The combined waves would alternately appear to be loud and faint with a period of 0.25 s.
c) The observer would hear a loud sound that has a frequency of 438 Hz.
d) The observer would hear two tones, one with a frequency of 436 Hz and one with a frequency of 440 Hz.
e) The observer would alternately hear a tone of frequency 436 Hz and one of frequency 440 Hz.

11. 17.4.2. Complete the following statement: The phenomenon of beats occurs when an observer
a) listens to two tones with slightly different frequencies.
b) listens to two tones with the same frequency, but are exactly out of phase with each other.
c) listens to two tones with the same frequency, but with different amplitudes.
d) listens to two tones with the same frequency, but are exactly in phase with each other.
e) listens to two tones with very different frequencies and amplitudes.

12. 17.4.3. Under what conditions can you hear beats of sound waves?
a) when the wave is a standing wave
b) when the wave is refracted
c) when the wave is diffracted
d) when two waves of slightly different frequency combine
e) when two waves of slightly different amplitude combine

13. 17.4.4. Which one of the following superpositions will result in beats?
a) the superposition of waves that are identical except for slightly different amplitudes
b) the superposition of waves that are identical except for slightly different frequencies
c) the superposition of identical waves that travel in the same direction
d) the superposition of identical waves that travel in opposite directions
e) the superposition of waves that travel with different speeds

14. A string has one end attached to a wall and the other end attached to a motor that moves the end up and down in simple harmonic motion. The frequency of the motor is varied until a transverse standing wave is produced on the string that has four nodes. Which of the following statements concerning this situation is false?
a) This standing wave has three antinodes.
b) This standing wave is produced by linear superposition of identical waves traveling in opposite directions.
c) This standing wave represents the third overtone.
d) This standing wave represents the third harmonic.
e) This standing wave occurs at a frequency that is 1.5 times greater than the frequency where a standing wave with three nodes is observed.

15. 17.5.2. What is the distance between two successive antinodes of a standing wave?
a) one-fourth wavelength
b) one-half wavelength
c) one wavelength
d) two wavelengths
e) four wavelengths

16. Which one of the following quantities is not a factor in determining the natural frequency of a string fixed at its two ends?
a) length
b) mass
c) tension
d) acceleration due to gravity

17. 17. 5. 4. A standing wave is set up on a taut string
A standing wave is set up on a taut string. Which of the following are not observed to move along the string?
a) nodes
b) antinodes
c) nodes and antinodes
d) Both nodes and antinodes can be observed moving along the string.
e) Nodes and antinodes can be observed switching positions at the natural frequency of the string.

18. A standing wave is produced in a vertical tube with both ends open. Complete the following sentence: Inside the tube, air molecules are
a) moving up and down about their undisturbed positions.
b) moving left and right about their undisturbed positions.
c) each oscillating between the bottom and the top of the tube.
d) only located in some regions of the tube and not others.
e) uniformly distributed throughout the tube at all times.

19. Which of the following parameters is not a factor in determining the natural frequency of a tube open at both ends?
a) length of the tube
b) speed of sound
c) wavelength of the sound wave
d) source of the sound
e) air temperature

20. 17. 6. 2. A sound wave is generated in a tube that has one closed end
A sound wave is generated in a tube that has one closed end. Which one of the following statements is false?
a) The natural frequency of the tube depends on its length.
b) A node occurs at the open end.
c) A node occurs at the closed end.
d) Odd harmonics are typically observed in such tubes.
e) Energy is conserved when a standing wave is produced in such tubes.

21. Complete the following statement: The sound waves corresponding to a concert A note (f = 440 Hz) by a flute are
a) complex sound waves.
b) identical to that produced by a trumpet playing the same note.
c) an example of a pure tone.
d) composed of one harmonic only.

22. Which one of the following statements explains why a piano and a guitar playing the same musical note sound different?
a) The fundamental frequency is different for each instrument.
b) The two instruments have the same fundamental frequency, but different harmonic frequencies.
c) The two instruments have the same harmonic frequencies, but different fundamental frequencies.
d) The two instruments have the same fundamental frequency and the same harmonic frequencies, but the amounts of each of the harmonics is different for the two instruments.