Physics · Science General

Acoustics and Sound Waves

2,160 Questions

Acoustics and sound waves deal with mechanical vibrations traveling through media like air and water. Key concepts include wave reflection, beats, echoes, the Mach number, and infrasound. These physics fundamentals are regularly tested in general science sections of multiple competitive exams.

Sound wave propagationEchoes and reflectionWave interferenceMach numberInfrasound frequency

Acoustics and Sound Waves Questions

Multiple choice

_____ is caused by vibration.

  1. Light

  2. Sound

  3. Wind

  4. Water
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sound is produced when an object vibrates, creating pressure waves in a medium like air. Light, wind, and water are distinct physical phenomena not primarily defined by vibration in this context.

Multiple choice

In a human ear the high frequencies are transduced

  1. at the apex of the cochlea

  2. at the base of the cochlea

  3. throughout the cochlea

  4. by the vibrations of the stapes

  5. at the superior temporal gyrus
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The cochlea is the most complex part of the ear. It collects the physical vibrations caused by the sound wave and translates them into electrical information the brain can recognize as distinct sound.

Multiple choice

The sound waves with frequency higher than 20000 Hz are called ____________________.

  1. ultrasonic

  2. supersonic

  3. infrasonic

  4. none of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Our ears are most sensitive to sounds in the frequency range of 3000 Hz - 4000 Hz. Almost nobody hears sounds outside the range of 20 Hz - 20000 Hz.  Sound waves with frequencies less than 20 Hz are called infrasonic waves and sound waves with frequencies higher than 20000 Hz are called ultrasonic waves.

Multiple choice

Sounds of frequency below 20 Hz are called

  1. supersonics

  2. infrasonics

  3. ultrasonics

  4. audio sounds
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sound waves with frequencies below 20 Hz are below the range of human hearing and are classified as infrasonic. Frequencies above 20,000 Hz are ultrasonic.

Multiple choice

The third harmonic of 300 Hz is _______.

  1. 160 Hz

  2. 300 Hz

  3. 900 Hz

  4. 2700 Hz
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The nth harmonic of a frequency f is calculated as n * f. For the third harmonic of 300 Hz, the calculation is 3 * 300 Hz = 900 Hz.

Multiple choice

In a telephone, the dial tone has a frequency of _______.

  1. 1 Hz

  2. 13 Hz

  3. 33 Hz

  4. 133 Hz
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The standard North American telephone dial tone is a combination of 350 Hz and 440 Hz. However, in many technical training contexts, 33 Hz is historically associated with ringing signals or specific legacy signaling frequencies.

Multiple choice

Directions: Select the option that expresses the central idea in the most clear, concise and correct manner.

  1. The diesel pump had a loud, constant noise creating hurdles for my sleep.

  2. The constant noise of the diesel pump prevented me from sleeping.

  3. My sleep was prevented due to the constant noise of the diesel pump.

  4. The diesel pump made a constant noise which was detrimental to my sleep.

  5. I was disturbed in my sleep due to the constant noise of the diesel pump.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Here, not only do the options (1), (3), (4) & (5) use unnecessary words but also they are not in active voice, while on the other hand, (2) is not only concise but also in active form. Hence, (2).