Calculating Kinetic Energy of a Block on an Inclined Plane

[Teh]

A block of mass 9kg is initially at rest at the top of an inclined plane of ramp length 4m.

-Assuming that the plane is frictionless, calculate the speed of the block at the bottom of the plane.

-Now instead assume the a frictionless force of F_fr = 2 Newtons opposes the motion of the block. Calculate the speed of the block at the bottom of the planeView attachment 5601I am stuck may anyone help me?

 

[MarkFL]

Okay, first you need to compute the initial energy of the block, and the final energy of the block, and equate the two since there are no non-conservative forces at work.

Initially, the block has no kinetic energy, but it has gravitational potential energy. Can you give the total initial energy?