(adsbygoogle = window.adsbygoogle || []).push({}); This is the problem:

A 15.0 kg box is slid down a 6.00 meter high ramp to pick up speed to do a vertical loop-the-loop whose radius is 2.00 meters. All surfaces are conveniently frictionless.

Part A)asks to find the Speed at the top of the loop-the-loop.

Part B)asks to find the Normal force on the box at the top of it's motion.

I'm just not sure I've solved it correctly.

Here's what I did it:

A)

PE_{i}+ KE_{i}= PE_{f}+ KE_{f}

(1/2)*m*v_{i}^{2}+ m*h_{i}*g = (1/2)*m*v_{f}^{2}+ m*h_{f}*g

0 + 6mg = (1/2)*m*v_{f}^{2}+ 4*m*g

6g = v_{f}^{2}/2 + 4g

v_{f}= sqrt(4g) =6.26m/s

B)Normal = Centripedal Force - mg = m*v^{2}/r - mg = 15*(6.26^{2}/2) - 15*9.8 =117.6 N

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# Homework Help: Problem calculating speed at the top of a loop-the-loop

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