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

A small mass m slides down from rest at the top of a frictionless spherical surface of radius R=.5 meters. What is the speed of the particle at position x where it loses contact with the surface, and velocity makes an angle of θ=48.2 with the vertical?

The answer choices are:

(A) 1.28 m/s

(B) 1.82 m/s

(C) 1.93 m/s

(D) 2.36 m/s

(E) 2.58 m/s

2. Relevant equations

Conservation of Energy?

3. The attempt at a solution

I thought maybe start with PE_{1}=PE_{2}+KE, where h=2r, and then find the cosine component of the height when velocity is at that angle, to do: mg(2r)=(1/2)mv^{2}+mg((cos48.2)+R), but that didn't work. I got .57, which is not even close to any of the choices.

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# Conservation of Energy/Motion Question

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