1. | Pressure | 2. | Density of gas |
3. | Above both | 4. | None of the above |
The speed of sound in a medium is \(v.\) If the density of the medium is doubled at constant pressure, what will be the new speed of sound?
1. | \(\sqrt{2} v \) | 2. | \(v \) |
3. | \(\frac{v}{\sqrt{2}} \) | 4. | \(2v\) |
A bat emits an ultrasonic sound of frequency \(1000\) kHz in the air. If the sound meets a water surface, what is the wavelength of the reflected sound? (The speed of sound in air is \(340\) m/sec and in water is \(1486\) m/sec)
1. \(3.4 \times 10^{-4}~\text{m}\)
2. \(1 . 49 \times 10^{- 3} ~ \text{m}\)
3. \(2 . 34 \times 10^{- 2} ~\text{m}\)
4. \(1 . 73 \times10^{- 3} ~\text{m}\)
The velocity of sound in air is:
1. | faster in dry air than in moist air. |
2. | directly proportional to the pressure. |
3. | directly proportional to temperature. |
4. | independent of the pressure of air. |
\(4.0~\text{gm}\) of gas occupies \(22.4~\text{litres}\) at NTP. The specific heat capacity of the gas at a constant volume is \(5.0~\text{JK}^{-1}\text{mol}^{-1}.\) If the speed of sound in the gas at NTP is \(952~\text{ms}^{-1},\) then the molar heat capacity at constant pressure will be:
(\(R=8.31~\text{JK}^{-1}\text{mol}^{-1}\))
1. | \(8.0~\text{JK}^{-1}\text{mol}^{-1}\) | 2. | \(7.5~\text{JK}^{-1}\text{mol}^{-1}\) |
3. | \(7.0~\text{JK}^{-1}\text{mol}^{-1}\) | 4. | \(8.5~\text{JK}^{-1}\text{mol}^{-1}\) |
1. | the frequency increases, and wavelength decreases. |
2. | the frequency remains constant, but the wavelength decreases. |
3. | the frequency decreases, wavelength remains constant. |
4. | the frequency remains constant but the wavelength increases. |
Assertion (A): | Sound travels faster on a hot summer day than on a cold winter day. |
Reason (R): | The velocity of sound is directly proportional to the square root of its absolute temperature. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |