Starting from rest, a 5.00 kg steel sphere rolls down a frictionless ramp with a height of 4.00 m. What is the sphere's speed when it reaches the bottom of the ramp? (Use 9.80 for the value of "g.") WHAT FORMULA DO I NEED TO USE ??????

Question

irishboy123 · Answer

its potential energy at top 

$mgh $ should equal its kinetic energy at the bottom 

$ \frac{1}{2} m v^2 + \frac{1}{2} I \omega^2$

you will need its radius to do that, and the formula for the moment of inertia of  sphere about its centre

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