Question

A proton with kinetic energy `K`, strikes another proton at rest. If the collision is head-on, find the correct graph between `K` and the distance of closest approach, `r`.
A.
B.
C.
D.

Answer 1

Correct Answer - C
At closets approach, both protons will be moving with same velocity.
`DeltaK.E=(1)/(2)mv_(0)^(2)-2.(1)/(2)m((v_(0))/(2))^(2)=(e^(2))/(4pi in_(0)r)`
`(1)/(4)mv_(0)^(2)=(e^(2))/(4pi in_(0)r)=(K)/(2)`
`Kr=(e^(2))/(2 pi in_(o))="constant", K alpha=(1)/(r )`