conservation of energy

[guru]

A 40 g ball is released from rest 2m above the bottom of a track. It rolls down a straight 30-degree segment, then back up a parabolic segment whose shape is given by y=(1/4)x^2, where x and y are in m. How high will the ball go on the right before reversing direction and rolling back down?

Have no clue how to start this problem.

[vsage]

how much potential energy does ball originally have? It can't lose any more energy going up the parabolic side than it gained from being dropped from 2m up.

[Sirus]

You can do this problem without any calculations. Apply the law of conservation of total mechanical energy:
E_{mechanical~initial}=E_{mechanical~final}
E_{potential~initial}+E_{kinetic~initial}=E_{poten tial~final}+E_{kinetic~final}