Q. 14.6( 11 Votes )
Suppose a charged particle moves with a velocity v near a wire carrying an electric current. A magnetic force, therefore, acts on it. If the same particle is seen from a frame moving with velocity v in the same direction, the charge will be found at rest. Will the magnetic force become zero in this frame? Will the magnetic field become zero in this frame?
Answer :
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.
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