Solve Whistle Frequency Homework: 11 Beats/s, 769 Hz, Answer in m/s

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To solve the problem, the frequency of the whistle is 769 Hz, and the beat frequency is 11 beats/s, leading to a perceived frequency of 780 Hz. The Doppler Effect is applied to determine the speed of the person moving towards the wall. The calculation involves using the formula for the Doppler shift to find the speed in m/s. The final answer should be presented as a numerical value with two significant figures.
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Homework Statement



You blow a whistle of frequency 769 Hz, as you move towards a wall.

The frequency of beats you hear from the whistle and the reflected sound is 11 beats/s.

How fast are you moving towards the wall?

Give your answer in m/s and to two significant figures.

Only answer in numerical values, no units.



Homework Equations





The Attempt at a Solution




769 + 11 = 780hz. Which I believe is the new frequency

Now what?
Thanks in advance
 
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You should use the Doppler Effect.
 
Thanks I got it
 

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