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
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high frequency and high amplitude
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high frequency and low amplitude
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low frequency and high amplitude
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low frequency and low amplitude
B
Correct answer
Explanation
If a sound is high-pitched and feeble, the sound wave has high frequency and low amplitude.
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increases
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decreases
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remains the same
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None of these
B
Correct answer
Explanation
In Doppler effect, when the sound source moves away from the receiver at rest, the frequency of sound that is heard decreases.
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light waves only
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sound waves only
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both sound and light waves
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neither light nor sound waves
C
Correct answer
Explanation
Doppler effect is applicable to both sound and light waves.
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resonance
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beats
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bass
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treble
D
Correct answer
Explanation
A group of sound waves having high pitch is known as treble.
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20 – 20,000 Hz
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40 – 120,000 Hz
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60 – 65,000 Hz
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15 – 50,000 Hz
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None of these
B
Correct answer
Explanation
The normal frequency range of hearing in a bat is 40 - 120, 000 Hz.
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Amplitude
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Frequency
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Speed
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Loudness
B
Correct answer
Explanation
Frequency determines the pitch of a sound.
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Only (a)
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Both (b) and (c)
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Both (a) and (b)
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Only (c)
A
Correct answer
Explanation
Echoes are heard due to successive or multiple reflections.
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Echo
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Vibrations
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Reverberations
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All of the above
B
Correct answer
Explanation
Sound is produced when a body vibrates in a medium.
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Megaphone
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Stethoscope
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Two persons talking in a small room
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A theatre with curved ceiling
C
Correct answer
Explanation
The phenomenon of reflection of sound is involved in the use of megaphone, stethoscope used by doctors and in a theatre with curved ceiling. Two persons talking to each other in a small room do not employ reflection of sound.
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0 – 20 Hz
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20 – 20,000 Hz
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Beyond 20,000 Hz
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0 – 20,000 Hz
C
Correct answer
Explanation
Frequencies higher than 20 kHz, i.e. 20,000 Hz are associated with ultrasonic sounds or ultrasounds.
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Both a and b
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Both b and c
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Both a and c
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Only a
B
Correct answer
Explanation
Ultrasonic waves have the tendency to travel in a straight line and have high penetration power. Thus, ultrasonic waves are preferred for industrial applications.
C
Correct answer
Explanation
Sound cannot travel through vacuum.
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Straight line
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Transversal wave motion
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Longitudinal wave motion
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Rotatory wave motion
C
Correct answer
Explanation
Sound travels as longitudinal waves where particles oscillate parallel to the direction of wave propagation. This creates regions of compression and rarefaction as the wave moves through a medium.
B
Correct answer
Explanation
Sound is a mechanical wave that requires a medium to propagate - it travels by vibrating particles in solids, liquids, or gases. A vacuum has no particles to vibrate, so sound cannot travel through it. This is why sound cannot travel through space.
D
Correct answer
Explanation
Sound is a mechanical wave that requires a medium (solid, liquid, or gas) to propagate. A vacuum is the absence of any medium, so sound cannot travel through it. Sound can travel through water, steel, and air, making vacuum the only correct answer.