Free Speed of Sound MCQs with Answers

• A. air
• B. water
• C. steel
• D. vacuum

Explanation: Sound travels fastest in solids because their particles are closely bound and pass on a disturbance quickly, giving about 5000 m per…

• A. the pressure alone increases at constant temperature
• B. the temperature increases
• C. the humidity falls
• D. the frequency of the sound increases

Explanation: Speed rises by roughly 0.61 m per second for every degree Celsius, because hotter molecules move faster and transmit the disturbance more…

• A. Soundlogy
• B. Acoustics
• C. Neurology
• D. Physiology

Explanation: Acoustics is the branch of physics that studies sound, including its production, transmission and properties.

• A. The speed of sound
• B. The speed of other object
• C. The speed of light
• D. The speed of air resistance

Explanation: Mach number is the ratio of an object's speed to the local speed of sound: Mach number = object speed (m/s) ÷ sound speed (m/s).

• A. 60 db
• B. 80 db
• C. 100 db
• D. 120 db

Explanation: The threshold of pain is conventionally taken to be about 120 dB, corresponding to a very large sound intensity compared with the…

• A. 4 : 1
• B. 1 : 1
• C. 2 : 1
• D. 1 : 2Educational Resources

Explanation: For a gas at constant temperature, the speed of sound is independent of pressure because v = √(γRT/M), which contains temperature and gas…

• A. 313°C
• B. 586°C
• C. 819°C
• D. 1172°C

Explanation: For a gas, sound speed is proportional to the square root of absolute temperature.

• A. 20000 to 30000 hertz
• B. 10 to 20 hertz
• C. 2000 to 4000 hertz
• D. 6000 to 8000 hertz

Explanation: The human ear is most sensitive to frequencies around 2000 to 4000 Hz, where the threshold of hearing is lowest.

• A. 1.61 ms-1
• B. 61.0 ms-1
• C. 0.61 ms-1
• D. 2.00 ms-1

Explanation: Near ordinary temperatures, the speed of sound in air increases by approximately 0.61 m s^-1 for every 1 °C rise in temperature.

• A. Two times
• B. Three times
• C. Four time
• D. Six time

Explanation: For a gas, sound speed is proportional to 1/√M when the other conditions are comparable.

• A. 281m/sec
• B. 333m/sec
• C. 340m/sec
• D. all of the above

Explanation: Newton used an isothermal model for sound propagation in air and obtained an estimate of about 281 m s-1.

• A. Water
• B. air
• C. copper
• D. ammonia

Explanation: Sound travels fastest in copper because its particles are closely packed and the material has a high elastic modulus, allowing vibrations…

• A. 332 ms-1
• B. 320 ms-1
• C. Zero
• D. 224 ms-1

Explanation: Sound is a mechanical wave and requires particles to transmit vibrations, but a vacuum contains no material particles.

• A. adiabatic
• B. isothermal
• C. isobaric
• D. isochoric

Explanation: Newton assumed that the compressions and rarefactions of sound in air occur under isothermal conditions, so heat has time to flow and the…

• A. Density of solids is high and elasticity is low
• B. Both density and elasticity are low
• C. Density is low and elasticity is high
• D. Elasticity of solids is very high

Explanation: Here is the explanation of the correct optionThe velocity of sound is greater than in gases primarily because solids have much higher…

• A. I only.
• B. III only.
• C. I and II.
• D. II and III.

Explanation: The speed of sound in a medium is influenced by both the density and elasticity of the medium.

• A. I only.
• B. III only.
• C. I and II.
• D. II and III.

Explanation: The velocity of sound is affected by temperature because sound travels faster in warmer air, due to the increased speed of air molecules.

• A. Varies unpredictably.
• B. Remains the same as the original sound.
• C. Becomes less than the frequency of the original sound.
• D. Becomes greater than the frequency of the original sound.

Explanation: When a fire brigade approaches a stationary listener, the sound waves from the siren are compressed, causing the listener to perceive a…

• A. Increases.
• B. Decreases.
• C. Becomes zero.
• D. Remains unchanged.

Explanation: The Doppler effect describes the change in frequency of a wave in relation to an observer who is moving relative to the wave source.

• A. Intensity
• B. Loudness
• C. Amplitude
• D. Velocity

Explanation: The correct answer is Velocity. The velocity of sound in air is affected by changes in air temperature because sound travels through the…