Question

A negative charge is coming towards the observer. The direction of the magnetic field produced by it will be (as seen by observer)
a) Clockwise
b) Anti-clockwise
c) in the direction of motion of charge
d) in the direction opposite to the motion of charge

Answer 1

"A negative charge is coming towards the observer.

The direction of the magnetic field produced by it will be in a clockwise direction.

Magnetic field = μ0i/ 4*pi (d1 * r)/ mod r^3

Here B is the direction of the i (d1 * r)

Hence, the charge is negative, i = -qdt

Put the value in the equation,

B is along –qdt (d1 *r) along – (d1 *r)

Hence the observer will see the magnetic field in a clockwise direction.

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