(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 2.0x10^2 g pendulum bob is raised 22cm above its rest position.The bob is released, and it reaches its maximum speed as it passes the rest position.

Calculate its maximum speed at that point by applying the law of conservation of energy and assuming that the efficiency is 100%.

2. Relevant equations

-eg=mgh

-ek=(mv^2)/2

-et=eg+ek

-eff=eoutput/einput x 100%

3. The attempt at a solution

-m=2.0 x 10^2 = 0.200 kg

-h=22cm=0.22 m

I know the law of conservation states when energy is changed from one form to another no energy is lost.

I tried using ek=(mv^2)/2 but I didn't know what ek so I coulden't solve for V.

eg=mgh

eg=(0.200kg)(9.8)(0.22)

eg=0.4312 j

I dont know what to do from here

eg=(

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# Homework Help: Law of conservation, and efficiency problem?

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