A mobile-phone charger is plugged into a 230 V, 50 Hz mains socket. The charger delivers 5 V to the phone and is marked 1 A maximum output current.
a. (i) Identify whether the transformer inside the charger is a step-up or a step-down device. Give reasons referring to the relative values of voltage and current in its windings.
b. (ii) Explain why the iron core of such a transformer is made of thin, insulated laminations rather than a solid block of iron.
c. (iii) A student states, “The transformer in the charger creates electrical energy for the phone battery.” Correct the statement with suitable reasoning.