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Question: An infinitely long cylinder is kept parallel to a uniform magnetic field \[B\] directed along the po...

An infinitely long cylinder is kept parallel to a uniform magnetic field BB directed along the positive z-axis. The direction of induced current on the surface of the cylinder as seen from the z-axis will be
A. Clockwise of the positive z-axis
B. Anticlockwise of the positive z-axis
C. Zero
D. Along the magnetic field

Explanation

Solution

When a compass is brought near the current-carrying conductor, the compass needle started deflecting because of the electricity. This statement shows that electric current produces a magnetic field. In a uniform magnetic field, the net velocity of the electron will be zero.

Formula used
From Maxwell equation: dBdt=E\dfrac{{d\overrightarrow B }}{{dt}} = - \nabla E

Complete step by step solution:
In question, it is given that we have a uniform magnetic field around the z-direction

From Maxwell equation dBdt=E\dfrac{{d\overrightarrow B }}{{dt}} = - \nabla E
We can say that changing the magnetic field generates an electric field and that will produce an electric current. But when the magnetic field is uniform then the velocity of the electron will be zero and there will be no electric field so
I=0I = 0
Therefore, The direction of induced current on the surface of the cylinder as seen from the z-axis will be zero. So, option (C) is correct .

Note:
In the early days, scientists believed that electricity and magnetism were two separate forces. But, after the discovery of the Maxwell equation by James Clerk Maxwell, these forces are treated as interrelated forces.
By the property of electromagnetism, the light wave can travel through a vacuum.
Machines like a fan, washing machine, refrigerator, television all work due to electricity. When current passes through the current-carrying conductor or coil, a magnetic field gets produced around that conductor or coil.
The spinning and orbiting of the nucleus of an atom produce a magnetic field similar to electrical current flowing through a wire. The direction of the spin and orbit decide the direction of the magnetic field.