The figure shows a graph of electric potential versus position along the x-axis. An proton is originally at point A, moving along in the positive x-direction. How much kinetic energy does the proton need to have at point A in order to be able to reach point E ( with no forces acting on the proton other than those due to the indicated potential)? How much kinetic energy does the electron need? Points B, C, and D have to be passed on the way.(adsbygoogle = window.adsbygoogle || []).push({});

I don't have a copy of the graph, but

A = 100 V

B = 0 V

C = -60 V

D = -20 V

E = 55 V

Okay so I know that since positive charges move through decreases in potential, and the potential and potential energy are greatest at A, the proton will spontaneously travel from point A to point E. So, Ka = 0.

But I'm really not sure how to calculate the kinetic energy for the electron. If someone could help me out, I'd appreciate it!!!

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# Conservation of Energy and electric potential

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