Question

distinguish between short circuiting and over loading

Answer 1

Short Circuit occurs when neutral wire and live wire touch accidentally providing a very low resistance path for current. ... Overloading of the circuit occurs when large number of appliances are connected in a single socket. This causes a large amount of current to flow and the fuse may blow off.

Answer 2

Think about the terms. An overload condition is precisely that - similar to a winch attempting to pick up a load beyond its rated capacity, or a weightlifter attempting to pick up more than he can handle. He might fight with it for a few seconds, but eventually he’ll lose.

Electrically, an overload condition exists when the impedance of a circuit is reduced to a point where more than the designed level of current is drawn. A short-circuit event is when the impedance drops to essentially zero and the MAXIMUM available current is drawn.