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2 years ago

9

A truck is traveling at 74.5 kilometers per hour away from you. The driver is blowing the horn which has a frequency of 415 Hz.

The speed of the sound is 346 m/s. What is the observed frequency of the sound? 346 Hz 392 Hz 415 Hz 441 Hz

2 answers:

Amanda [17]2 years ago

6 0

Answer: option D is the answer!

slega [8]2 years ago

5 0

$\frac{415}{f} = \frac{346- \frac{745}{36} }{346+0}$
f=441.40

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Answer:

Part a)

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Part b)

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Part c)

$\theta = -127.7 degree$

Explanation:

As we know that acceleration is rate of change in velocity of the object

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Part a)

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Now the acceleration of the object is given as

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at t= 1.1 s we have

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Part b)

Direction of the force is given as

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$tan\theta = \frac{-5.22}{-5.74}$

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Part c)

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now the direction of the velocity is given as

$\theta = tan^{-1}(\frac{v_y}{v_x})$

$\theta = tan^{-1}(\frac{-12.8}{-9.89})$

$\theta = -127.7 degree$

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