Atrain moving at a constant speed is passing a stationary observer on a platform. on one of the train cars, a flute player is continually playing the note known as concert a (f = 440 hz). after the flute has passed, the observer hears the sound with a frequency of 415 hz. what is the speed of the train? the speed of sound in air is 343 m/s.

Explanation:

We shall apply the formula of Doppler effect here

F( APPARENT) = F( REAL ) X V/(V + Vs) [ v is velocity of sound and Vs is velocity of source.

415 = 440 X 343/343+Vs

142345 + 415Vs = 150920

415 V₀ = 8575

V₀ = 20.66 m/s.

sonar - device which is used to find the submit submarines, sankalp ship. sonar waves consists of a transmitter and detector which are installed in the observation centre on board of a ship. the ultrasonic waves are sent into the sea at high frequency about 1000 khz in all direction.

explanation:

newton's third law, for every action there is an equal and opposite reaction.