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प्रश्न
Answer briefly.
State the expression for apparent frequency when source of sound and listener are
- moving towards each other
- moving away from each other
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उत्तर
- Let, n0 = actual frequency of the source.
n = apparent frequency of the source.
v = velocity of sound in air.
vs = velocity of the source.
vL = velocity of the listener. - Apparent frequency heard by the listener is given by, n =`"n"_0 (("v" +- "v"_"L")/("v" bar+ "v"_"s"))`
Where upper signs (+ ve in numerator and -ve in denominator) indicate that the source and observer move towards each other. Lower signs (-ve in numerator and +ve in denominator) indicate that the source and listener move away from each other. - If source and listener are moving towards each other, then apparent frequency is given by,
n = `"n"_0(("v" + "v"_"L")/("v" - "v"_"s"))` i.e., apparent frequency increases. - If source and listener are moving away from each other, then apparent frequency is given by,
n = `"n"_0(("v" - "v"_"L")/("v" + "v"_"s"))` i.e., apparent frequency decreases.
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संबंधित प्रश्न
In discussing Doppler effect, we use the word "apparent frequency". Does it mean that the frequency of the sound is still that of the source and it is some physiological phenomenon in the listener's ear that gives rise to Doppler effect? Think for the observer approaching the source and for the source approaching the observer.
The engine of a train sounds a whistle at frequency v. The frequency heard by a passenger is
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Answer briefly.
What is Doppler effect?
State the expression for apparent frequency when listener is stationary and source is moving towards the listener.
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
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