Question

Faraday's experiment: Describe the rate of change of the current in a primary solenoid at different points in a given cycle. What effect would this have had on the magnetic flux passing through the secondary solenoid?

Answer 1

When the switch is closed, there is a potential difference between the terminals of the primary coil. The current in the primary coil has grown from zero to some value (maximum value) and therefore the corresponding magnetic flux around magnetic circuit changes from zero to some value. During this changing situation, from no current to some steady state current, the changing magnetic flux in the core induces an emf in the secondary coil and hence there is change in current in secondry coil.