Suppose a charged

Formula used:

The magnetic force is given by

Where F is magnetic force

q is electric charge =

v is velocity

Angle between magnetic force and velocity component

A Charge particle is moving near a conducting wire. And also a frame is moving in the same direction which the charge is moving. Seeing from the frame it is known that the charge is at rest. So velocity of the charge particles will be zero. Thus magnetic force will be zero.

When the charge is at rest the current will be zero. We don’t know either it is a positive or negative charge. Let us consider it is a negative charge. Seeing from the frame negative charge is at rest. But there is a positive charge flow. Due to this magnetic field will exists. So the magnetic field should not be zero.