A sound wave travelling in air is made to propagate through a liquid such that the velocity of sound is quadrupled. If the frequency of the sound wave is constant, find the change in the wavelength of the sound wave

Explanation

(i) When sound moves through different media, will its frequency (m) change? Find how many times the velocity of sound in air (`V_1`) increases when made to pass through liquid (`V_2`). Then, take velocity, wavelength of sound in air and liquid as `V_1, lamda_1, V_2, lamda_2,` respectively. Here, `V_1 = n lamda_1` and `V_2 = lamda_2` is `V_2 = 4V_1` Substitute (2) in (1) and find the relation between `lamda_1` and `lamda_2`. Now, find the change in `lamda `., i.e., `( lamda_2- lamda_1)` (ii) Increase in wave length is thrice the initial wave length