physics
posted by Sejul .
A 20. kg block is placed at the top of a 10. meterlong inclined plane. The block starts from rest and slides without friction down the length of the incline. (A diagram shows a height of 5.0 m, the 10. m length of incline/hypotenuse and the 20. kg block sliding on the hypotenuse.)
1) find the gravitational potential energy of the block at the TOP of the incline.
2) Find the kinetic energy of the block just as it reaches the bottom of the incline.
How do I set this up?

1)PE=mgh
PE=20 kg(9.81m/s^2)(5m)
PE=981 J
2)The kinetic energy should be 981 J because its frictionless and energy should be conserved.