Question

explain what is short circuiting an electric supply

Answer 1

short circuit is simply a low resistance connection between the two conductors supplying electrical power to any circuit. This results in excessive current flow in the power source through the 'short,' and may even cause the power source to be destroyed. If a fuse is in the supply circuit, it will do its job and blow out, opening the circuit and stopping the current flow. 

Answer 2

When the live and neutral wire come in contact with each other due to some fault or due to bad insulation, short circuit occurs. It can also occur if the appliance itself is faulty.
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