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Question
An e.m.f is produced in a coil, which is not connected to an external voltage source. This can be due to ______.
- the coil being in a time varying magnetic field.
- the coil moving in a time varying magnetic field.
- the coil moving in a constant magnetic field.
- the coil is stationary in external spatially varying magnetic field, which does not change with time.
Options
a, c and d
a, b and d
b, c and d
a, b and c
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Solution
a, b and c
Explanation:
As we know whenever the number of magnetic lines of force (magnetic flux) passing through a circuit changes, an emf is produced in the circuit called induced emf. The induced emf persists only as long as there is a change or cutting of flux.
In this problem, magnetic flux linked with the isolated coil changes when the coil is placed in the region of a time-varying magnetic field, the coil moving in a constant magnetic field or in time-varying magnetic field.
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