How far from equilibrium will a 45 g mass with amp. of .35 m for a spring (k = 21 N/m) undergoing simple harmonic motion have a speed that is half its maximum velocity?(adsbygoogle = window.adsbygoogle || []).push({});

a. .3 m

b. .45 m

c. .7 m

d. .92 m

e. 3.5 m

Choice B is wrong.

Use

v = v_max*sqrt[1 - (x^2/A^2 m)]

Do I use k or m at all???

(1/2)v_max = v_max*sqrt[1 - (x^2/A^2 m)]

Left with:

1/2 =sqrt[1 - (x^2/A^2 m)]

After plugging everything in and solving for x I get .303m (A.). Am I wrong?

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# Homework Help: Vibrations and Waves

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