If the birds sit on electric wires they don’t get a shock. Why?

Birds sitting on electric wires don’t get shocked because-

1. In order to flow electricity, any circuit must be closed and here the circuit is incomplete as the bird is not in contact with any other wire. Here, it has no potential difference as both the legs of the bird are touching the same wire at the same constant potential. If the bird will touch another wire of different resistance at the same time, then the circuit becomes complete and the flow of charge takes place from high voltage to low voltage, allowing the electricity to travel through the bird’s body. Then the bird gets a shock.

2. The wires in the electric wires are usually made of Aluminum or Copper which are very good conductors of electricity. Electrons/charge prefer to flow through a substance having better conductivity (lesser resistance). The claws of birds sitting on an aluminium/copper wire are not good conductors of electricity so they don’t offer an easier way to flow current through them. Hence electricity bypasses the birds and keeps flowing through the wire.

Usually, all the birds sit on any one of the electrical wires, so, they won’t get shocked even when their tail touches the other wire, because their feather is the bad conductor of electricity.