Question

While discussing the propagation of sound through atmospheric air, one argued that the velocity of sound is 280 ms^-1 and said that he calculated it using Newton’s formula. But another learner argued that velocity of sound is 330 ms1. He justified his argument by saying that he has applied Laplace corrected formula.

1. Write the formula used by the second learner.

2. Using the above relation, show that velocity depends on temperature and humidity while is independent of pressure.

3. “Sound can be heard over longer distance on rainy days.” Justify.

Answer 1

1. a = \(\sqrt{\frac{2λP}{ρ}}\)

2. 

If temperature remain same

PV = constant

∴ v is independent of p.

3. During rainy day as ρ decreases. Hence v increase and sound propagate longer distance.