Question

A source of sound of frequency 450 cycles/sec is moving towards a stationary observer with 34 m/sec speed. If the speed of sound is 340 m/sec, then the apparent frequency will be

• A. 410 cycles/sec
• B. 500 cycles/sec
• C. 550 cycles/sec
• D. 450 cycles/sec

Answer 1

Answer: (B)

500 cycles/sec

Answer 2

$n' = n\left( \frac{v}{v - v_{0}} \right) = 450\left( \frac{340}{340 - 34} \right) = 500cycles/\sec$