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Simple harmonic motion question (1 Viewer)

enigma_1

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The amplitude of a particle moving in SHM is 5 metres, and its acceleration when 2 metres from its mean position is 4m/s^2. find the speed of the particle at the mean position and when it is 4m from the mean position.

Answers:
5pi/2

5pi^2/8


thanks
 

braintic

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There is no way there can be pi's in the answer.
Are you sure you have the answer to the right question?

acc = -n^2 x

(ignoring -ve due to badly worded question)

4 = n^2 . 2
n^2 = 2

x=0:
v^2 = n^2 (a^2 - x^2)
=2 (5^2 - 0)
v=5√2

x=4:
v^2 = 2(5^2 - 4^2)
v=3√2
 

enigma_1

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Crap sorry, you're right, your answers are correct, thanks!
 

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