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I have an exercise to ask yourself.

A ball of mass m = 5 g starts at rest and travels 50 cm along a ramp inclined at 45 ° to the horizontal. a) If we imagine frictionless motion of the ball along the ramp, compute the speed of the ball at the bottom of the ramp. What is the change in potential energy of the ball?

My idea is to use the gravitational acceleration, multiply it by the cosine of $45°$ and find the x-component of the gravitational acceleration, and finally use the formula $ v^2=v_0^2 +2*g*x $ to find the speed at the end of the ramp.

For the second point, my idea is to use this formula $ m*g*h $.
My idea is correct?

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Yes, your ideas are good, they should get you the right answers. Be sure to take care when calculating the change in height for m*g*h. Does this answer your question?

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Yes! Thanks for your help! – DamianFox Jan 12 '13 at 14:48

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