What is the mutual inductance of a pair of coils if current changing at the rate of 50 A/s in one coil induces an EMF of 50 mV in the other coil? What will be the secondary voltage produced by a...

What is the mutual inductance of a pair of coils if current changing at the rate of 50 A/s in one coil induces an EMF of 50 mV in the other coil?

What will be the secondary voltage produced by a transformer which has 400 primary turns and 100 secondary turns, when there is an alternating voltage input to the primary of 240 V?