Tag: range of hearing

Questions Related to range of hearing

Multiple choice physics range of hearing sound: production of sound audible, infrasonic and ultrasonic sounds different sounds

Which one has higher frequency?

  1. <span>Infrasonic sound</span>

  2. <span>Ultrasonic sound</span>

  3. Audible sound

  4. All of the above have same frequency

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ultrasonic frequency is above audible range means above $20KHz$ and infrasonic frequency is below the audible range which means below $20 Hz$.

so the answer is B

Multiple choice physics range of hearing sound: production of sound audible, infrasonic and ultrasonic sounds different sounds

The property of ultrasonic waves used in manufacturing emulsion for photographic films is its, _____________

  1. High speed

  2. High frequency

  3. Higher wavelength

  4. High amplitude

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The property of ultrasonic waves in manufacturing emulsion for photographic films in its high frequency. The frequency of ultrasonic wave is above $20 KHz$

Multiple choice physics range of hearing sound: production of sound audible, infrasonic and ultrasonic sounds different sounds

The grandparents and parents of two-year old girl are playing with her in a room. A sound source produces a $28 kHz$ sound. Who in the room is most likely to hear the sound?

  1. Grandparent

  2. &nbsp;Little girl

  3. Both

  4. None of them

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The frequency range of hearing in infants is more than in adult. As the infant gets mature, this range decreases. So two year girl will be more likely to hear that sound.
So the answer is B.
Multiple choice physics range of hearing sound: production of sound audible, infrasonic and ultrasonic sounds different sounds

The sound intensity is 0.008 $W/m^2$ at a distance of 10 m from an isotropic point source of power of the source is approximately :

  1. 2.5 watt

  2. 0.8 watt

  3. 8 watt

  4. 10 watt

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Intensity I = P / (4 * pi * r^2). Given I = 0.008 and r = 10, P = I * 4 * pi * r^2 = 0.008 * 4 * 3.14 * 100 = 0.008 * 1256 = 10.048 watts, which is approximately 10 watts.

Multiple choice physics range of hearing sound: production of sound audible, infrasonic and ultrasonic sounds different sounds

The driver of a car travelling at the speed of $30m/sec$ towards a hill sounds a horn of frequency $600\ Hz$. If the velocity of sound in air is $330m/s$, the frequency of reflected sound as heard by the driver is

  1. $500\ Hz$

  2. $550\ Hz$

  3. $555.5\ Hz$

  4. $720\ Hz$

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The frequency heard by the hill is f' = f * (v / (v - vs)) = 600 * (330 / (330 - 30)) = 600 * (330 / 300) = 660 Hz. This reflected sound acts as a source moving towards the driver, so f'' = f' * ((v + vo) / v) = 660 * ((330 + 30) / 330) = 660 * (360 / 330) = 720 Hz.

Multiple choice physics range of hearing sound: production of sound audible, infrasonic and ultrasonic sounds different sounds

Ultrasonic, intrasonic and audible waves travel through a medium with speeds $V _u,V _i,$ and $V _a$ respectively, then (given constant temperature)

  1. $V _i=V _a=V _u$

  2. $V _u&gt;V _a&gt;V _i$

  3. $V _u &lt; V _a &lt; V _i $

  4. ${ V } _{ a }\le { V } _{ u }={ V } _{ i }$

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The speed of sound in a medium depends on the properties of the medium (density, elasticity) and temperature, not on the frequency of the sound wave.