1.

A person with vibrating tuning fork of frequency 338 Hz Is moving towards a vertical wall with a speed of 2 ms^(-1) . Velocity of sound in air is 340 ms^(-1) . The number of beats by that person per second is :

Answer»

2
4
6
8

Solution :The frequency of sound heard by person after reflection upon the WALL is
`v. = ((v+ u_(0))/(v - u_(0))) ` v
= `((340 + 2)/(340 -2)) 338 `
= 342 Hz.
`THEREFORE` No. of beats heard by the person= v. - v
= 342 - 338
= 4 Hz.
So CORRECT choice is b.


Discussion

No Comment Found

Related InterviewSolutions