Question

A proton is fired toward a lead nucleus from very far away. How much initial kinetic energy does the proton need to reach a turning point 10 fm from the nucleus?

Answer 1

Answer:

The electric force is conservative.

Since

ΔK = −ΔU,

Kf − Ki =Ui −Uf.

We have,

Kf = 0

Ui = 0.

Thus Ki =Uf.

so ,at 10 fm Uf = (2×10)−12 J.