Posted by Jessie on .
A block is sent up a frictionless ramp along which an x axis extends upward. The figure below gives the kinetic energy of the block as a function of position x; the scale of the figure's vertical axis is set by Ks = 46.0 J. If the block's initial speed is 4.50 m/s, what is the normal force on the block?
I got 44.5 N but this was wrong. How would I go about correctly solving this?

Physics urgent 
Jessie,
Any and all help would be appreciated. I have an exam coming up and I can't seem to crack this particular problem