Question

What is induced EMF produced in a given figure?

Answer 1

Hint: For electromagnetic induction, the velocity, Magnetic field, and length of the conductor must be mutually perpendicular to each other. If any two are parallel to each other, then no current will be induced. Therefore, zero EMF will induce.

Complete answer:
In the given figure the cube is moving with the velocity v in the same direction of magnetic field, B.

Formula for induced EMF is-
$E=vlBsin\theta$
Where, v is the velocity of the conductor.
L is the length of the conductor.
B is the magnetic field.
$\theta$ is the angle between the magnetic field and the motion of the conductor.
In the figure, the cube has twelve edges of length l. Each edge will behave as a conductor.
All the twelve conductors are moving parallelly to the magnetic field. So,
$\theta =0^{\circ }$
$E=vlBsin0$
$E=0$.
No induced EMF will generate as v and B are parallel to each other.
So, moving cube has zero induced EMF.

Additional Information:
EMF can induce in two significant ways, either due to a conductor's motion in the presence of a magnetic field or due to the difference in the magnetic flux surrounded by the circuit.

Note:
When a conductor is placed into a magnetic field, EMF induces because of the effective interaction with the magnetic field, but the force on electrons in any branch of the cube is zero. Hence, no emf will be induced. The induced current's direction is such that the current reverses the change that caused it.