Question

Coil 1 has L1= 25 mH and N1= 100 turns. Coil 2 has L2= 40 mH and N2= 200 turns. The coils are fixed in place; their mutual inductance M is 3.0 mH. A 6.0 mA current in coil 1 is changing at the rate of 4.0 A/s. (a) What magnetic flux f12 links coil 1, and (b) what self-induced emf appears in that coil? (c) What magnetic flux f21 links coil 2, and (d) what mutually induced emf appears in that coil?