Q. Two coils are at fixed locations. When coil 1 has no current and the current in the coil 2 increases at the rate 15.0 $As^{- 1}$, the emf in coil 1 is 25.0 mV. When coil 2 has no current of 3.6 A. The flux linkage in coil 2
A) 4 mWb
B) 6 mWb
C) 10 mWb
D) 16 mWb
Explanation
(b) As $e = M\frac{di}{dt}$
$\therefore\ \ M = \frac{e}{di/dt} = \frac{25 \times 10^{- 3}}{15.0} = 1.67 \times 10^{- 3}$H
As $\phi\ = Mi$
$\therefore\ \phi = 1.67 \times 10^{- 3} \times 3.6 = 6 \times 10^{- 3}$ Wb
= 6 m Wb
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.