Question

An electron and proton are projected with same velocity in a region having uniform magnetic field perpendicular to the velocity. Then which of the following is correct

1) Electron will describe a smaller circle
2) Proton will describe a smaller circle
3) Electron will have greater time period of revolution
4) Proton will have greater frequency of revolution

Well the answer is 1) but please tell why and become the brainliest.​

Answer 1

Heya Friend,

When an electron and proton are projected with same velocity in a region having uniform magnetic field perpendicular to the velocity:-

1) Electron will describe a smaller circle.

Description]. We know, F=qvB ---(1).

F=m(v)^2/r----(2)

From (1) and (2), Left hand sides are equal, now we have,

qvB = m(v)^2/r

From above equation, we get,

m∝r.

The equation we obtained states that lesser would be mass of a particle the smaller radius it would be in.

Now, electron has lesser mass tends that it will move in smaller circular path.

Hence, we proved Option 1). is correct.

Hope it helps...