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प्रश्न
The engine of a train sounds a whistle at frequency v. The frequency heard by a passenger is
विकल्प
\[> v\]
\[< v\]
\[= \frac{1}{v}\]
\[= v\]
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उत्तर
\[= v\]
For the Doppler effect to occur, there must be relative motion between the source and the observer. However, this is not the case here. Hence, the frequency heard by the passenger is υ.
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संबंधित प्रश्न
Answer briefly.
What is Doppler effect?
Answer briefly.
State the expression for apparent frequency when the source is stationary and the listener is
- moving towards the source
- moving away from the source
Answer briefly.
State the expression for apparent frequency when source of sound and listener are
- moving towards each other
- moving away from each other
Solve the following problem.
A police car travels towards a stationary observer at a speed of 15 m/s. The siren on the car emits a sound of frequency 250 Hz. Calculate the recorded frequency. The speed of sound is 340 m/s.
Explain red shift and blue shift in Doppler Effect.
Discuss the following case-
Observer in motion and Source at rest.
- Observer moves towards Source
- Observer resides away from the Source
Discuss the following case-
Both are in motion
- Source and Observer approach each other
- Source and Observer resides from each other
- Source chases Observer
- Observer chases Source
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- the frequency of sound as heard by an observer standing on the platform is 400 Hz.
- the speed of sound for the observer standing on the platform is 350 m/s.
- the frequency of sound as heard by the observer standing on the platform will increase.
- the frequency of sound as heard by the observer standing on the platform will decrease.
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A source and a detector move away from each other in absence of wind with a speed of 20 m/s with respect to the ground. If the detector detects a frequency of 1800 Hz of the sound coming from the source, then the original frequency of the source considering the speed of sound in air 340 m/s will be ______ Hz.
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When an observer moves towards a stationary source with velocity 'V₁', the apparent frequency of emitted note is 'F₁'. When observer moves away from stationary source with velocity 'V₁' the appearent frequency is 'F2'. If 'v' is velocity of sound in air and \[\frac {F_1}{F_2}\] = 2, then \[\frac {V}{V_1}\] is equal to ______.
