At a regional substation connected to the National Grid, a step-down transformer is used to reduce the transmission voltage from 132 kV132\text{ kV}132 kV to 11 kV11\text{ kV}11 kV for local distribution. A simplified diagram of this transformer setup is shown below:
Explain, in terms of magnetic fields and electromagnetic induction, how an alternating current in the high-voltage (132 kV132\text{ kV}132 kV) primary winding produces an alternating current in the low-voltage (11 kV11\text{ kV}11 kV) secondary winding when connected to a closed external circuit.