The distance between two points on a wave that have the same amplitude and motion is called

A) Period

B) Frequency

C) Amplitude

 D) Wavelength

As a wave crosses a boundary between mediums, it travels from a less “dense” (high permittivity) medium to a more “dense” (low permittivity) medium. Which of the following properties of the wave change?

A) Speed

B) Wavelength

C) Amplitude

D) All of these.

Which of the following mediums is not able to transmit sound waves?

A) Vacuum

B) Water

C) Air

D) Steel

A) Vacuum

. As the pitch of a sound is increasing, what property of the sound wave is increasing?

A) Amplitude

B) Wavelength

C) Frequency

D) Speed

According to the Doppler Effect, if a police car sounding its siren is moving away from you, the siren’s pitch will be? as compared to when the police car is stationary while it sounds its siren

A) Lower

B) Higher

C) the same

 D) None of these.

1. Infrasonic
1. time it takes for one complete back and forth vibration
2. term that refers to how high or low sound frequencies appear to be
3. term applied to sound pitch too low to be heard by the human ear, that is, below 20 Hz
4. The speed of a wave is equal to its wavelength multiplied by its frequency.

1. natural frequency
1. Violet light has the greater frequency
2.  a frequency at which an elastic object, once energized, will vibrate
3. time it takes for one complete back and forth vibration
4. crest overlaps crest or a trough overlaps a trough

1. If a wave vibrates up and down twice each second and travels a distance of 20 m each second, what is its frequency? Its wave speed? 
1. When a wave source moves toward a receiver, the receiver encounters an increase in wave frequency, but not in wave speed.
2. If a wave vibrates up and down twice each second and travels a distance of 20 m each second, its frequency is 2 Hz, and its wave speed is 20 m/s. This question is better answered by carefully reading the question rather than searching for a formula because all of the information needed is given in the question.
3. the distance from the midpoint to the crest of the wave
4. a disturbance in air in which pressure is lowered; opposite of compression

1. If you triple the frequency of a vibrating object, what will happen to its period? (No Answer)
1. a pulse of compressed air; opposite of rarefaction
2. a frequency at which an elastic object, once energized, will vibrate
3. the distance from the midpoint to the crest of the wave
4. If you triple the frequency of a vibrating object, its period will decrease by a factor of 3.

1. When watching a baseball game, we often hear the bat hitting the ball after we actually see the hit. Why? (No Answer)
1. the distance between successive identical parts of the wave
2. We hear the bat hitting the ball before after we actually see the hit because light travels faster than sound.
3. a frequency at which an elastic object, once energized, will vibrate
4. the distance from the midpoint to the crest of the wave

1. What is the relationship between forced vibration and resonance? (No Answer)
1. the distance from the midpoint to the crest of the wave
2. If you triple the frequency of a vibrating object, its period will decrease by a factor of 3.
3.  Resonance occurs when the frequency of a forced vibration on an object matches the object's natural frequency and an increase in amplitude occurs.
4. a phenomenon that occurs when the frequency of forced vibrations on an object matches the object's natural frequency, and a dramatic increase in amplitude results

1. How does interference of sound relate to beats? (No Answer)
1. term that refers to how high or low sound frequencies appear to be
2. the distance between successive identical parts of the wave
3. the distance from the midpoint to the crest of the wave
4.  The interference of two sound sources of slightly different frequencies produces beats.

1. As the frequency of sound is increased, does the wavelength increase or decrease? Give an example.

1. wavelength:
1. time it takes for one complete back and forth vibration
2. She should further tighten the string.
3. crest overlaps a trough
4.  the distance between successive identical parts of the wave

1. a. In dry air at room temperature, sound travels at about 340 m/s.
   b. For each degree increase in air temperature above 0 degrees C, the speed of sound in air decreases by 60 m/s.

1. vibration
   
1. crest overlaps a trough
2.  a wiggle in time
3. She should further tighten the string.
4. a wiggle in space

1. amplitude
   
1. She should further tighten the string.
2. the distance from the midpoint to the crest of the wave
3. the distance between successive identical parts of the wave
4. Violet light has the greater frequency.

1. compression 
1. a pulse of compressed air; opposite of rarefaction
2. Violet light has the greater frequency.
3. crest overlaps crest or a trough overlaps a trough
4. crest overlaps a trough

1. period 
1. a pulse of compressed air; opposite of rarefaction
2. the distance from the midpoint to the crest of the wave
3. time it takes for one complete back and forth vibration
4. She should further tighten the string.

1. longitudinal wave (No Answer)
1. the distance from the midpoint to the crest of the wave
2. the medium moves at right angles to the direction in which the wave travels
   ex. electromagnetic waves, such as light and radio waves
3. time it takes for one complete back and forth vibration
4. the medium moves back and forth parallel to the direction in which the wave travels
   ex. sound waves

If the frequency of a particular wave is 20 Hz, its period is

A.  1/20 second.

A.  1/20 second.

The vibrations along a transverse wave move in a direction

A.  along the wave.

Which signal will be heard first?

A.  Radio signal.

None of the above

Compared with a dry road, seeing is difficult when driving at night on a wet road. Why?

A.  Wet surface is smooth with less diffuse reflection, part of which would otherwise reach the driver’s eyes.

Interference is a property of

A.  sound.

Neither of these

When a fire engine approaches you, the

A.  speed of its sound increases.

The Doppler effect occurs for

A.  sound.

When we consider the distance a pendulum swings to and fro, we’re talking about its:

If the frequency of a particular wave is 30 Hz, its period is

In Europe, alternating electric current vibrates to and fro 50 cycles in 1 s. The frequency of these vibrations is

D) 1/50 Hz with a period of 1/50

If you dip your finger repeatedly onto the surface of still water, you produce waves. The more frequently you dip your finger,

When sound or light undergoes interference, it can sometimes

What does NOT occur with the Doppler effect are changes in

A sonic boom is the result of wave