The difference in the speeds of sound in air at `-5^@C`, 60 cm pressure of mercury and `30^@C`, 75 cm pressure of mercury is (velocity of sound in air at `0^@C` is `332(m)/(s)`)

Options

A. `15.25(m)/(s)`
B. `21.35(m)/(s)`
C. `18.3(m)/(s)`
D. `3.05(m)/(s)`

Answer

B

Explanation

Velocity of sound is not affected by the change inpressure of air. Velocity of sound at `1^@C`,
`v_1=(332+0.61t)(m)/(s)`
At `-5^@C`,`v_(-5^@C)=(332-0.61xx5)(m)/(s)`
At `30^@C`,`v_(30^@C)=(332+0.61xx30)(m)/(s)`
`v_(30^@C)-v_(-5^@C)=(0.61xx35)(m)/(s)`
`=21.35(m)/(s)`