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2 years ago

15

What frequency is received by a person watching an oncoming ambulance moving at 110 km/h and emitting a steady 800-Hz sound from

its siren? The speed of sound on this day is 345 m/s.

1 answer:

Strike441 [17]2 years ago

8 0

To develop this problem we will apply the concepts related to the Doppler effect. The frequency of sound perceive by observer changes from source emitting the sound. The frequency received by observer $f_{obs}$ is more than the frequency emitted by the source. The expression to find the frequency received by the person is,

$f_{obs} = f_s (\frac{v_w}{v_w-v_s})$

$f_s$ = Frequency of the source

$v_w$ = Speed of sound

$v_s$ = Speed of source

The velocity of the ambulance is

$v_s = 119km/h (\frac{1000m}{1km})(\frac{1h}{3600s})$

$v_s = 30.55m/s$

Replacing at the expression to frequency of observer we have,

$f_{obs} = 800Hz(\frac{345m/s}{345m/s-30.55m/s})$

$f_{obs} = 878Hz$

Therefore the frequency receive by observer is 878Hz

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Plugging the numbers into the equation, we find
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2 years ago

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Explanation:

From the question we are told that

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2 years ago

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Maurinko [17]

Answer:

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As we know that the velocity of the tip of the kicker's shoe is given as

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Part c)

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erica [24]

Explanation:

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(II). The image is inverted.

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2 years ago

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I don't think its a niche or community.My best guess is probably the habitat.
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2 years ago

Read 2 more answers