SOUND QUIZ-7th

The image below shows air particles in a sound wave produced by a drummer. Which best describes the wave modeled in the image?

• This is a longitudinal wave because the air particles move back and forth, parallel to the direction the wave travels.

• This is a transverse wave because the air particles move back and forth, in the direction the wave travels.

• This is a longitudinal wave because the air particles move up and down, perpendicular to the direction the wave travels.

• This is a transverse wave because the air particles move up and down, perpendicular to the direction the wave travels.

The image below shows air particles in a sound wave produced by a drummer. What effect does beating the drum faster have on the frequency and wavelength of the sound wave?

• Both the frequency and wavelength increase.

• The frequency decreases and the wavelength increases.

• The frequency increases and the wavelength decreases.

• Both the frequency and wavelength decrease.

The image below shows air particles in a sound wave produced by a drummer. How does the image change if the drum is beaten harder?

• There are more particles in the compressions and fewer particles in the rarefactions.

• There are more particles in the rarefactions and fewer particles in the compressions.

• There are more particles in both compressions and rarefactions.

• There are fewer particles in both compressions and rarefactions.

A student places a large jar over a phone that is on a smooth flat surface. The jar is then connected to a vacuum pump. When the pump is turned on, air is slowly sucked out of the jar. Another student then calls the phone inside the sealed jar. Which best explains what happens?

• The volume of the phone’s ring decreases.

• The volume of the phone’s ring increases.

• The volume of the phone’s ring is unchanged.

• The volume of the phone’s ring decreases and then increases.

The image below shows the human respiratory system and the vocal cords. Which statement best explains why a person’s voice often is lower in pitch when they have a cold?

• The vocal cords become swollen which causes them to vibrate faster.

• The vocal cords become dried out and thinner which causes them to vibrate faster.

• The vocal cords become swollen which causes them to vibrate slower.

• The vocal cords become dried out and thinner which causes them to vibrate slower.

Which statement best explains the data?

• A) Air particles move faster as the temperature increases.

• B) Air particles move slower as the temperature increases.

• C) Air particles compress more as the temperature increases.

• D) Air particles stick together less as the temperature increases.

The image below shows sound waves being used to detect an underwater object. Which property has the greatest effect on the time required for the reflected wave to return to the ship?

• water temperature

• size of the object

• clarity of the water

• shininess of the object

According to this data, which sound is 100 times less loud than the sound at a concert?

• Fireworks

• Hair dryers

• Jet planes during take off

• Motorcycles

A person at a concert is seated 20 m away from the stage speakers. If the student moves to a new location, 100 m away, what fraction of the original intensity of the sound produced by the speakers will the student hear?

Which of the following will you hear as a high pitch?

• sound wave with a frequency of 10,000 Hz

• sound wave with a frequency of 50 Hz

• sound wave with an intensity of 10 dB

• sound wave with an intensity of 100 dB