A charge moving with velocity `v` in `X`-direction is subjected to a field of magnetic induction in the negative `X`-direction. As a result, the charge will

Options

A. remain unaffected
B. start moving in a circular Y-Z plane
C. reatard along X-axis
D. move along a helical path around X-axis

Answer

A

Explanation

Force on a charged particle, moving in a magnetic field is given by `F = q v B sin theta`

But the angle between v and B is `180^(@) and sin 180^(@)=0`
`therefore G =qv B sin 180^(@)=0`
`therefore` The charge remains unaffected.