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प्रश्न
A source of sound is travelling with a velocity 40 km/h towards an observer and emits a sound of frequency 2000 Hz. If the velocity of sound is 1220 km/h, then the apparent frequency heard by the observer is _____.
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उत्तर
A source of sound is travelling with a velocity 40 km/h towards an observer and emits a sound of frequency 2000 Hz. If the velocity of sound is 1220 km/h, then the apparent frequency heard by the observer is 2068 Hz.
Hint:
Apparent frequency heard by the observer.
Data:
v = 1220 km/h (or) 339 ms-1
vS = 40 km/h (or) 11.1 ms-1
n = 2000 Hz
n' = `("v"/("v"-"v"_s))` n
= `(339/(339-11.1))` x 2000
= 1.03385 x 2000
= n' = 2068 Hz.
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