Each of two persons has a whistle of frequency 500 Hz . One person is at rest at a particular place nad the second person recedes from him with a velocity of1.8 m * s^(-1) If both of them blow whistles , how many beats will be heard by each of them ? Velocity of sound= 330 ms^(-1)

Each of two persons has a whistle of frequency 500 Hz . One person is

1.	Each of two persons has a whistle of frequency 500 Hz . One person is at rest at a particular place nad the second person recedes from him with a velocity of1.8 m * s^(-1) If both of them blow whistles , how many beats will be heard by each of them ? Velocity of sound= 330 ms^(-1)
Answer» Solution :Both of them listen to the sound of frequency 500 Hz form their own WHISTLES . In the first case , let us suppose that the first person is listenting to the sound coming from the whistle of the second person . Here the velocity of the listener , ` u_(o) = 0 ` Since the source is receding , the velocity of the source , ` u_(s) = - 1.8 * s^(-1)` ` therefore` Apparent frequency , ` n. = (V)/(V - u_(s)) XXN = (330)/(330 - (-1.8)) xx 500 = 497.29` Hz ` therefore ` NUMBER of beats per second ` = n- n. = 500 - 497.29` ` = 2. 71 ~~3 ` In the second case , let us suppose that the second person is listening to the sound coming from the whistle of the first person. Here the velocity of the source , ` u_(s) = 0 ` Since the listener is receding , The velocity of the listener , ` u_(0) = - 1.8 * s^(-1)` ` therefore ` Apparent frequency , ` n. = (V + u_(o))/(V) xxn = (330 - 1.80/(330 ) xx 500 = 497.27 Hz` ` therefore ` Number of beats per second = n - n. = 500 - 497.27 ` = 2.73 ~~ 3`