Waves and Sound 2C

Which best describes sound waves?

• c. Positive displacement of particles

• a. Transfer of energy from one place to another

• b. Transfer of mass from one place to another

• d. Movement in a direction perpendicular to the direction of the wave

Which statement is false, as suggested by the universal wave equation 𝑣 = 𝑓�

• a. If the frequency is held constant, the speed increases as the wavelength increases.

• b. Speed is the product of the frequency and the wavelength

• c. If the wavelength is held constant, the speed increases as the frequency decreases. .

• d. If the speed is held constant, wavelength increases as the frequency decreases

Which of the following actions will increase the speed of sound in air?

• a. Decreasing the air temperature

• b. Increasing the frequency of the sound

• c. Increasing the air temperature

• d. Increasing the amplitude of the sound wav

If one crest has a 3 cm amplitude and interacts with another wave to produce a crest 8 cm high this demonstrates:

• a) constructive interference

• b) destructive interference

• c) Doppler Effect

• d) a node

What will be the result if a crest with an amplitude of 30 cm overlaps a trough with an amplitude of 5.0 cm?

• a) crest with an amplitude of 35 cm

• b) trough with an amplitude of 35 cm

• c) crest with an amplitude of 25 cm

• d) trough with an amplitude of 25 cm

Two tuning forks of frequencies 3l0 and 3l6 Hz vibrate simultaneously. The number of times the resulting sound pulsates per second (beats) is:

• a) 0

• b) 6

• c) 313

• d) 626

Beats are the result of:

• a) diffraction

• b) constructive interference

• c) destructive interference

• d) both constructive and destructive interference

A dust particle is suspended in the air (floating) when a powerful loudspeaker plays a very low note. How will the dust particle move as a result of the speaker being turned on? (see diagram to the right)

• a) The dust particle will move up and down

• b) The dust particle will be pushed across the room.

• c) The dust particle will move side to side.

• d) The dust particle will move in a circular path. e) The dust particle will not move at all.

When a police car with its siren on is approaching you, the sound of the siren will be

• a) slightly louder than normal.

• b) slightly higher in pitch than normal.

• c) slightly quieter than normal.

• d) slightly lower in pitch than normal.

The amplitude of a sound wave corresponds to its:

• a) pitch

• b) loudness

• c) frequency

• d) resonance