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BartSMP [9]
3 years ago
14

Two cars approaching each other , first car moves at 72 km/h ,the second car moves at 90 km/h,the first car started its siren wi

th a frequency of 650 Hz. If the speed of the sound is 350 m/s, then what is the frequency of the sound heard by the driver of the second car from the police car?
Physics
2 answers:
Iteru [2.4K]3 years ago
6 0

Answer:

Because the speed of sound travels at +- 1300 km/h and the car that is approaching isn't that fast. So u first hear the sound before the car reaches u.

i hope it helps

Explanation:

Kay [80]3 years ago
3 0

Answer:

Observed Frequency by Second Car = 739 Hz

Explanation:

Vs = 72km/h = 20m/s (Divide by 3.6)

Vo = 90km/h = 25m/s

f = 650[(350+25)/(350-20)]

f = 739 Hz

Best Regards: Your Friendly Study Co-Pilot

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