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Enlighten Me!

Why Birds sitting on a wire are shock proof?

We often see birds sitting comfortably on high-tension electric wires without getting hurt.
This may seem surprising, but the reason lies in how electricity flows. For a shock to occur,
a significant current must pass through the body. In the case of a bird, almost no current

flows through it.

Firstly, a bird’s body offers high resistance compared to the wire. Just as we would choose
to walk on a smooth road rather than a pothole-filled one, electric current also takes the
easier path. The smooth path is the wire, not the bird’s body, so current continues to flow
through the wire.

Secondly, and more importantly, the bird faces almost no voltage difference across its
body. Electricity flows when there is a difference in potential (voltage) between two points.
Since both of the bird’s feet are on the same wire, the potential difference between them is
practically zero. With no significant voltage difference, there is no driving force for current

to pass through the bird’s body.

However, danger arises if the bird touches two wires at once or touches the wire and
another object connected to the ground. In this case, there is a large potential difference
between the two points. Current would then flow through the bird’s body, causing a shock.

The greater the voltage difference, the stronger and more dangerous the current.

Thus, birds are safe on a single wire, but contact with multiple wires or grounded objects
can be fatal.

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