Question

The mutual inductance `M_(12)` of coil 1 with respect to coil 2
A. increases when they are brought nearer
B. depends on the current passing through the coils
C. increases when one of them is rotated about an axis
D. is the same as `M_(21)` of coil 2 with respect to coil 1

Answer 1

Correct Answer - A::D
When the coils are brought nearer, the flux linked with them increases, thus `M_(12)` is increased.
Again, `M_(12)=ksqrt(L_(1)L_(2))=M_(21)`