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

A train producing a siren with a frequency of 1500 Hz approaches a stationary observr with a speed of 72 kmph. What is apparent frequency of sound heard by him when it crossing him ?( Given velocity of sound v = 340ms^(-1) )

An echo was heard after 3 s what is the distance of the reflecting surface from the source given that the speed of sound in 342ms^(-1) ?

A train standing in a station yard, blows a whistle of frequency 400 Hz in still air. The wind starts blowing in the direction from the yard to the station with a s speed of 10ms^(-1) . What are the frequency , wavelength and speed of sound for an observer standing on the station's platform? Is the situation exactly identical to the case when the air is still and the observer runs towards the yard at a speed of 10 ms^(-1) ? The speed of sound in still can be taken as 340 ms^(-1)

A train standing a the outer signal of a railway station blows a whistle of frequency 400Hz in still air . when the train (i) approaches the platform with a speed of 10ms^(-1) ? (ii) recedes from the platform with a speed of 10 ms^(-1) ? What is the speed of sound in each case ? The speed of sound in still air can be taken as 340ms^(-1)

A car sounding its horn at 480 Hz moves towards a high wall at a speed of 20 ms^-1 . If the speed of sound is 340 ms^-1 , the frequency of the reflected sound heard by the passenger sitting in the car will be nearest to