An observer moves towards a stationary source of sound with a velocity one-fifth of the velocity of sound. What is the percentage increase in the apparent frequency ?

Options

A. 0.2
B. 0.05
C. 0.005
D. zero

Answer

A

Explanation

`(v.)/(v) = ((V+ U_(0))/(V)) = ( V + (1)/(5) V)/(V) = (6)/(5) `
`therefore ` % Increase = `(v. -v)/(v ) xx 100 = ((6)/(5) - 1) xx 100 = 20% `
correct choice is (a) .