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3 years ago

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Two trains on separate tracks move toward each other. Train 1 has a speed of 125 km/h; train 2, a speed of 94.0 km/h. Train 2 bl

ows its horn, emitting a frequency of 500 Hz. What is the frequency heard by the engineer on train 1?

1 answer:

dexar [7]3 years ago

4 0

Answer:

$f_{o}=595.98Hz$

Explanation:

Given data

Train 1 speed v₀=125 km/h =34.7222 m/s

Train 2 speed vs=94.0 km/h=26.1111 m/s

Speed of sound v=343 m/s

Train 2 frequency fs=500 Hz

To find

Frequency f₀ heard by engineer on train 1

Solution

We can use below formula to find the required frequency

$f_{o}=f_{s}(\frac{v+v_{o}}{v-v_{s}} )\\f_{o}=(500Hz)(\frac{343m/s+34.722m/s}{343m/s-26.111m/s} ) \\f_{o}=595.98Hz$

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