A coil is wound as a transformer of rectangular cross section. If all the linear dimension of the transformer are increased by a factor `2` and the number of turns per unit length of the coil remain the same, the self-inductance increased by a factor of

Options

A. 4
B. 8
C. 12
D. 16

Answer

B

Explanation

`L=(mu_(0)N^(2)pir^(2))/(l)=mu_(0)n^(2)pir^(2)l`
`Lprop("Linear terms")^(3)`