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aev [14]
3 years ago
15

From a vantage point very close to the track at a stock car race, you hear the sound emitted by a moving car. You detect a frequ

ency that is 0.86 times as small as the frequency emitted by the car when it is stationary. The speed of sound is 343 m/s. What is the speed of the car?
Physics
1 answer:
V125BC [204]3 years ago
6 0

Answer:

55.8 m/s

Explanation:

f = Actual frequency of sound emitted by car

f' = frequency observed when the car moves = (0.86)f

V = Speed of sound = 343 m/s

v = Speed of car

Frequency observed is given as

f' = \frac{Vf}{V+v}

(0.86) = \frac{(343)}{343 + v}\\(0.86) = \frac{(343)}{343 + v}\\294.98 + (0.86) v = 343 \\v = 55.8 ms^{-1}

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