Two conducting circular loops of radii `R_1 and R_2` are placed in the same plane with their centres coincidingt. Find the mutual inductane between them assuming `R_2ltltR_1`.

Options

A. `(-(1))/(R_(2))`
B. `(R_(2))/(R_(1))`
C. `(R_(1)^(2))/(R_(2))`
D. `(R_(2)^(2))/(R_(1))`

Answer

D

Explanation

Mutual inductance between two coils in the same plane with their centres coiciding is given by
`M=(mu_(0))/(4pi)((2pi^(2)R_(2)^(2)N_(1)N_(2))/(R_(1)))`