MEDIUM
JEE Main
IMPORTANT
Earn 100
A source of sound emitting a note of frequency moves towards an observer with a velocity equal to the velocity of sound. If the observer also moves away from the source with the same velocity , the apparent frequency heard by the observer is .
50% studentsanswered this correctly
Important Questions on Sound Wave And Doppler Effect
MEDIUM
JEE Main
IMPORTANT
A source of sound is travelling towards a stationary observer. The frequency of the sound heard by the observer is of three times the original frequency. The velocity of sound is . If the speed of the source is then _____.
MEDIUM
JEE Main
IMPORTANT
A source and listener are both moving towards each other with speed , where is the speed of sound. If the frequency of the note emitted by the source is , the frequency heard by the listener would be nearly _____. (Give solution in decimal with two decimal place accuracy).
MEDIUM
JEE Main
IMPORTANT
Two trains are moving towards each other at speeds of and relative to the ground. The first train sounds a whistle of frequency . The frequency of the whistle heard by a passenger in the second train before the train meets is _____ (The speed of sound in air is .)
MEDIUM
JEE Main
IMPORTANT
A car sounding a horn of frequency passes an observer. The ratio of frequencies of the horn noted by, the observer before and after passing of the car is . If the speed of sound is , If the speed of the car is then _____.
HARD
JEE Main
IMPORTANT
A boy is walking away from a wall towards an observer at a speed of and blows a whistle whose frequency is . The observer will hear _____ beats per second. (Velocity of sound in air )
MEDIUM
JEE Main
IMPORTANT
When an engine passes near to a stationary observer, then its apparent frequencies occur in the ratio . If the velocity of the engine is _____ .
HARD
JEE Main
IMPORTANT
In a car race sound signals emitted by the two cars are detected by the detector on the straight track at the endpoint of the race. Frequency observed are and and the original frequency is of both cars. The race ends with the separation of between the cars. Assume both cars move with constant velocity and velocity of sound is . Find the time taken by winning car.
HARD
JEE Main
IMPORTANT
A wall is moving with velocity and a source of sound moves with velocity in the same direction as shown in the figure. Assuming that the sound travels with velocity . Find the ratio of incident sound wavelength on the wall to the reflected sound wavelength by the wall.
