Doppler Effect with heart motion

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rpcarroll
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Homework Statement


Suppose a heart's ventricular wall moves in simple harmonic motion with amplitude 1.8mm and a frequency of 115 per minute. (a) Given a motion detector in contact with the chest produces sound at 2,000,000Hz which travels through tissue at 1.50 km/s. Find the maximum linear speed of the heart wall. (b) Find maximum frequency at which the sound arrvies at the heart. (c) Find the maximum frequency which at which sound is received by the motion detector.

Homework Equations


f'=fo((Vo+Vmax)/Vo)

The Attempt at a Solution


(a) 115=2,000,000((1.5+Vmax)/1.5)
Vmax=1.5
I am struggling with some of the concepts and where different terms can be applied, any suggestions? Do I need to convert any units?
 
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rpcarroll said:
... simple harmonic motion with amplitude 1.8mm and ... frequency of 115 per minute.
(a) Given ... sound at 2,000,000Hz ... travels through tissue at 1.50 km/s. Find the maximum linear speed of the heart wall. (b) Find maximum frequency at which the sound arrvies at the heart. (c) Find the maximum frequency ... at which sound is received by the motion detector.
The wording of (a) is quite confusing, but I think that you don't need the info about the motion detector. (b) is ambiguous, but I would imagine you need to take into acount the doppler effect. You will have to think about (c) a bit.



rpcarroll said:
(a) 115=2,000,000((1.5+Vmax)/1.5)
Vmax=1.5
I don't think so.