a submarine fitted with a SONAR system operates at a frequency 50kHz. An enwmy submarine is now moving towards it with a speed of 450km/hr. Find the frequency of the sound received back at the SONAR from the enemy submarine. Velocity of sound in water is 1450m/s.

Answer 1

the distance is closing, so the frequency is higher

F = 50kHz * [1450 / (1450 m/s - 450 km/hr)]

Answer 2

Thank you Sir. :)