Loudness and Amplitude

Physics ⇒ Waves and Sound

Loudness and Amplitude starts at 7 and continues till grade 12. QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Loudness and Amplitude. How you perform is determined by your score and the time you take. When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.

See sample questions for grade 11

A person increases the volume on a speaker. Which property of the sound wave is being changed?

A sound has an intensity of 1 × 10⁻⁶ W/m². Calculate its intensity level in decibels (dB) relative to the threshold of hearing.

A sound wave has an amplitude of 0.01 m and produces a loudness of 40 dB. What will be the loudness if the amplitude is increased to 0.02 m?

A sound wave has an amplitude of 0.02 m. If the amplitude is increased to 0.06 m, how does the loudness change?

A sound wave has an intensity of 1 × 10⁻⁴ W/m². What is its intensity level in decibels?

Describe how the human ear perceives changes in amplitude of a sound wave.

Describe the effect of distance from the source on the loudness of sound.

Explain the difference between loudness and intensity of sound.

Explain why loudness is considered a subjective property of sound.

Explain why two sounds with the same intensity may be perceived as having different loudness.

If a sound source moves closer to a listener, what happens to the perceived loudness?

If the amplitude of a sound wave is doubled, by what factor does its loudness increase?

If the intensity of a sound increases by a factor of 100, by how many decibels does the loudness increase?

If the intensity of a sound is 1 × 10⁻⁸ W/m², what is its loudness in decibels?

State the relationship between intensity (I) and amplitude (A) of a sound wave.

The threshold of hearing is defined as the quietest sound that can be heard by the average human ear. What is its intensity in W/m²?

A factory siren emits a sound with an intensity level of 90 dB at a distance of 10 meters. Assuming no energy loss to the environment, what would be the intensity level in dB at a distance of 100 meters from the siren?

A sound wave in air has an amplitude of 0.005 m and produces an intensity of 2.5 × 10⁻⁵ W/m². If the amplitude is tripled, what will be the new intensity of the sound wave?

A sound wave in water has a much higher intensity than a sound wave in air, but both are perceived as equally loud by a human listener. Explain why this is possible.

Explain why the loudness of a sound decreases as you move away from the source, even though the amplitude of the wave at the source remains constant.