Question

A charge q is moving with a velocity opposite to the direction of magnetic field force on the charge due to the magnetic field is

• A. 0
• B. qB/v
• C. qvB
• D. Bv/q

Answer 1

The correct option is A

0

Magnetic field:

1. It is the area around a magnet.
2. It follows the effect of magnetism.
3. It creates an electric current.
4. An example of it is Earth's magnetic field.

A diagram to represent the magnetic field:

The correct option is (A).

Explanation:

The magnetic force on a moving charge is $\overrightarrow{F}=q\overrightarrow{v}\times \overrightarrow{B}$

So, the force is perpendicular to both the velocity of the magnetic field B and charge q.

Here, the magnitude of the force is $F=qvB\sin \theta$

where, $\theta$ is the angle $=180°$ between the magnetic field and the velocity

Therefore, the magnetic force on a stationary charge or charge moving parallel to the magnetic field is zero.