Question

Why is the e.m.f. at consuming centers dropped to 220 V by a step-down transformer?

Answer 1

At the consuming centers, the high transmission voltage is very dangerous and cannot be used directly in homes, schools, factories, or other appliances. Domestic appliances and electrical devices are designed to operate safely at 220 V. Therefore, consumption centers use a step-down transformer to reduce the e.m.f. from the high transmission voltage to a safe 220 V.