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natali 33 [55]
3 years ago
5

An airplane traveling at half the speed of sound emits a sound of frequency 4.68 kHz. (a) At what frequency does a stationary li

stener hear the sound as the plane approaches? kHz (b) At what frequency does a stationary listener hear the sound after the plane passes? kHz
Physics
1 answer:
kkurt [141]3 years ago
6 0

Answer:

(a) 9.36 kHz

(b) 3.12 kHz

Explanation:

(a)

V = speed of sound

v = speed of airplane = (0.5) V

f = actual frequency of sound emitted by airplane = 4.68 kHz = 4680 Hz

f' = Frequency heard by the stationary listener

Using Doppler's effect

f' = \frac{Vf}{V-v}

f' = \frac{V(4680)}{V-(0.5)V)}

f' = 9360 Hz

f' = 9.36 kHz

(b)

V = speed of sound

v = speed of airplane = (0.5) V

f = actual frequency of sound emitted by airplane = 4.68 kHz = 4680 Hz

f' = Frequency heard by the stationary listener

Using Doppler's effect

f' = \frac{Vf}{V+v}

f' = \frac{V(4680)}{V+(0.5)V)}

f' = 3120 Hz

f' = 3.12 kHz

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Answer:

a) \Delta x=56.25 m

b) imagen adjunta

Explanation:

a) Primero debemos hacer la conversión de 81 km/h a m/s, esto es 22.5 m/s.

Ahora, usando la ecuacion cinemática, en un movimiento acelerado tenemos:

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\Delta x=\frac{-v_{0}^{2}}{2a}

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b) Para este caso el gráfico se encuentra adjunto.                                      

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