Question

A proton beam passes without deviation through a region of space where there are uniform transverse mutually perpendicular electric and magnetic field with `E` and `B` Then the beam strikes a grounded target. Find the force imparted by the beam on the target if the beam current is equal to I .

Answer 1

Correct Answer - `(mEI)/(Be)`
`oversetrarrF = 0implies oversetrarrF_(e) + oversetrarrF_(m) = 0 implies F_(e) = F_(m) implies qE = q V B`
`V =(E)/(B)....(1)`
`F = (dp)/(dt) = (Nmv)/(t) ...(2)`
`I =(Ne)/(t) implies t = (Ne)/(I) ..(3)`
From (1) (2) and (3) `F = (mEI)/(eB)` .