MEDIUM
11th ICSE
IMPORTANT
Earn 100

An engine is approaching a railway station at 5 m/s speed while sounding a whistle of 600 Hz frequency. What will be the frequency of the whistle as heard by an observer standing on the platform? Speed of sound is 340 m/s.
 

Important Questions on Doppler Effect

MEDIUM
11th ICSE
IMPORTANT
ISC Physics Class XI Part 1>Chapter 33 - Doppler Effect>NUMERICALS>Q 3

A source of sound is approaching a stationary listener with a speed of 166 m/s. The listener hears a sound whose apparent frequency is twice the real frequency. Find the speed of sound waves.

MEDIUM
11th ICSE
IMPORTANT
ISC Physics Class XI Part 1>Chapter 33 - Doppler Effect>NUMERICALS>Q 4
If to a stationary observer the apparent frequency of a moving source of sound appears 54 of its real frequency, then find the speed of the source and its direction of motion.
MEDIUM
11th ICSE
IMPORTANT
ISC Physics Class XI Part 1>Chapter 33 - Doppler Effect>NUMERICALS>Q 5
A source of sound moving towards a stationary observer with a certain velocity passes him with the same velocity. The ratio of the apparent frequencies when the source is moving towards the observer and when moving away from the observer is 75. Find the velocity of the source of sound.
HARD
11th ICSE
IMPORTANT
ISC Physics Class XI Part 1>Chapter 33 - Doppler Effect>NUMERICALS>Q 6
A whistling engine is approaching a stationary observer with a velocity of 110 m/s. Find the ratio of the apparent frequency of the whistle when the engine is going towards the observer to the frequency when the engine is going away from the observer.
HARD
11th ICSE
IMPORTANT
ISC Physics Class XI Part 1>Chapter 33 - Doppler Effect>NUMERICALS>Q 7
A train is moving towards a stationary observer with a speed of 30 m/s. The frequency of its whistle appears to be 600 Hz to the observer. If the train were moving away from the observer with the same speed, then what frequency of the whistle would have been listened ?
MEDIUM
11th ICSE
IMPORTANT
ISC Physics Class XI Part 1>Chapter 33 - Doppler Effect>NUMERICALS>Q 9
With what velocity should an observer go away from a stationary source of sound so that the frequency of the sound as heard by him is half of the actual frequency ?
HARD
11th ICSE
IMPORTANT
ISC Physics Class XI Part 1>Chapter 33 - Doppler Effect>NUMERICALS>Q 11
With what velocity should a source of sound travel towards a stationary observer so that the apparent frequency may be double of the actual frequency? Velocity of sound is 340 m/s.
HARD
11th ICSE
IMPORTANT
ISC Physics Class XI Part 1>Chapter 33 - Doppler Effect>NUMERICALS>Q 12
Two trains are approaching each other with the speeds of 72 km/h. The frequency of the whistle of one train as heard by a passenger on the other train is 700 Hz. Find : (i) the real frequency of the whistle before the trains meet and (ii) the frequency of the whistle heard by the passenger when the trains have crossed each other.