Question

A whistle giving out 450Hz approaches a stationary observer at a speed of 33m/s. The frequency heard by the observer in Hz is (speed of sound = 330m/s).

(a) 409

(b) 429

(c) 517

(d) 500

I got this question by my school teacher while I was bunking the class.

Asked question is from Transverse Waves in division Waves of Engineering Physics I

Answer 1

Right option is (d) 500

The explanation: v^‘=v/(v-vs)×v

v^‘=330/(330-33)×450=500Hz.