Question

1) Why do we see a deflection in the galvanometer, indicating current through the larger solenoid, when changing the amount of current through the smaller solenoid?

2)The faster the current in the smaller solenoid is changed, the greater the induced current in the larger solenoid. Why is this?

THANKS IN ADVANCE

Answer 1

We see a deflection in the galvanometer indicating current through the larger solenoid when changing the amount of current through the smaller solenoid due to the phenomenon of electromagnetic induction. The two solenoids have a finite coefficient of mutual inductance which means that whenever the current through one of the solenoid is changed then a corresponding change in the current of other solenoid will be observed which is due to the phenomenon of electromagnetic induction As given by Faraday and lenz law. We know that according to Faraday and lenz law the EMF induced ( or the current induced) is proportional to the rate of change of magnetic flux through a coil (solenoid).

2) now as stated above, the magnitude of EMF induced or the current induced is directly proportional to the rate of change of magnetic flux, therefore faster is the current changed in the smaller solenoid would result in greater induced EMF which ultimately results in greater induced current then the larger solenoid.

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