(a(i))[2]
Explain why an alternating current produces a heating effect in a resistor.
(a(ii))[2]
By referring to heating effect, what is meant by the root-mean-square (r.m.s.) value of an alternating current.
(b(i))[2]
State Faraday’s law of electromagnetic induction.
(b(ii))[3]
Use Faraday’s law to explain why the current in the primary coil is not in phase with the e.m.f. induced in the secondary coil.