Wave Mechanics Question 852

Question: It takes 2.0 seconds for a sound wave to travel between two fixed points when the day temperature is $ 10^{o} $ C. If the temperature rise to $ 30^{o} $ C the sound wave travels between the same fixed parts in

[Orissa JEE 2003]

Options:

A) 1.9 sec

B) 2.0 sec

C) 2.1 sec

D) 2.2 sec

Show Answer

Answer:

Correct Answer: A

Solution:

Suppose the distance between two fixed points is d then $ t=\frac{d}{v}\text{also }v\propto \sqrt{T}\Rightarrow \frac{t _{1}}{t _{2}}=\frac{v _{2}}{v _{1}}=\sqrt{\frac{T _{2}}{T _{1}}} $

Therefore $ \frac{2}{t _{2}}=\sqrt{\frac{303}{283}} $

$ \Rightarrow $ $ t _{2} $ = 1.9 sec.