Submarine `A` is going with speed of `18km//hr`. Submarine `B` is chasing `A` with speed of `27 km//hr`. It sends frequency of `500Hz` and hears after reflection from `A`. The perceived frequency is :
`(V_("sound in water")=1500m//s)`

The sirens of two ambulances have a frequency of 500 Hz each. An observer hears the sirem from the two engines, one approaching him with a speed of 18 km/hr and other going away from him at a speed of 36 km/hr. Determine the difference in frequency of two sirens heard by the observer. Take, speed of sound in air = 340 m/s.

The speed of train is 54km/hr. Find it in m/s

A sonar system fixed in a submarine operates at a frequency 40.0 kHz, An enemy subarine moves towords the sonar with a speed of 360 km/h. What is the frequency of sound refielcted by the submarine? (Take the speed of sound in water to be 1450 m/s)

A SONAR system fixed in a submarine operates at a frequency 50 kHz. It is moving towards a rocky hill present inside water with a speed of 432 km h^(-1) . What is the apparent frequency of sound observed at the submarine after reflection by the rocky hill ? (Take velocity of sound in water to be 1450 m s^(-1) )

A particle goes A to M with a speed of 30 km/hr. and M to B with a speed of 50 km/hr. If MB = 5AM, the average speed in km/hr for the whole journey is –

A SONAR system fixed in a submarine operates at a frequency 40.0kHz. An enemy submarine moves towards the SONAR with a speed of 360 km h^(-1) . What is the frequency of sound reflected by the submarine ? Take the speed of sound in water to be 1450 ms^(-1) .

A car travels from City A to City B at a speed of 40km/hr and from B to A at a speed of 60km/hr. What is the average speed of the car?