Three persons `P_(1), P_(2)`, and `P_(3)` are at three different points A, B and C as shown in the figure. `P_(1)` and `P_(2)` clap at the same time. For `P_(3)` to hear two distinct claps, the minimum distance between `P_(1)` and `P_(2)` should be _______ m. (The velocity of sound in air is `330 ms^(-1)`)

Options

A. 33
B. 330
C. 363
D. 660

Answer

A

Explanation

Human ear can hear two sounds separately only if they reach the ear after an interval of 1/10 of a second. So, the time taken by the sound from `P_1` to `P_2` should be greater than 1/10 s = 0.1 s. The distance between `P_1 and P_2`
` = v xx t = 330 xx 0.1 = 33 m`