In which of the following activities is an induction coil not useful?
Answer Details
An induction coil is not useful in A.C. power transmission.
An induction coil is a device that can produce high voltages by inducing a high voltage in a secondary coil through electromagnetic induction. It works on the principle of changing the magnetic field around a conductor to induce an electromotive force (EMF) in a nearby conductor.
In the investigation of high voltages, the induction coil is useful as it can produce very high voltages that are needed for some experiments. In the study of electric discharge, induction coils are used to create a spark in a gas-filled tube or bulb.
In the operation of X-ray tubes, induction coils are used to generate a high voltage potential difference between the cathode and anode of the tube. This voltage accelerates electrons towards the anode, causing X-rays to be produced.
However, in A.C. power transmission, the voltage is already alternating, and the transformer is used instead of an induction coil to increase or decrease the voltage level. A transformer works on the same principle of electromagnetic induction but can handle higher power levels and has more efficient energy transfer characteristics. Thus, an induction coil is not useful in A.C. power transmission.
Therefore, the correct answer is A.C. power transmission.