The magnetic flux linked with a coil is `phi` and the emf induced in it is `e`.

Options

A. If `phi=E` must be 0
B. If `phi ne 0` E cannot be zero
C. If E is not 0 `phi` may or may not be 0
D. none of the above is correct

Answer

C

Explanation

Induced emf,
`E=-(dphi)/(dt)`
Therefore `E=0` when `(dphi)/(dt)=0` and vice versa.
Even `if phi=0, (d phi)/(dt)` may be non-zero.
Similarly, if `phi ne0 (d phi)/(dt)` may be zero
For example if `phi= phi _(0) sin (omegat)`
Then `E=- (dphi)/(dt)=-phi_(0) cos (omegat)`