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While standing at a crosswalk, you hear a frequency of 510 Hz from an approaching police car.

After the police car passes, its frequency is 460Hz. What is the speed of the police car? (speed of
sound = 340 m/s)

User Technico
by
4.2k points

1 Answer

1 vote

Answer:

v = 17.68 m/s

Step-by-step explanation:

Given that,

While standing at a crosswalk, you hear a frequency of 510 Hz from an approaching police car.

After the police car passes, its frequency is 460Hz.

We need to find the speed of the police car.

The formula is as follows :


v=(v_o(f-f'))/(f+f')

Put all the values,


v=(343(510-460))/(510+460)\\\\=17.68\ m/s

So, the speed of the police car is 17.68 m/s.

User Jurgen Camilleri
by
4.0k points