The Resistant Roosters

The period of national lockdown has certainly increased the number of flying visitors to the town. Many different kinds of birds can be seen freely moving around in the rather smokeless skies of the city. Most of the birds can be found perching on top of the omnipresent electric wires in the neighbourhood. I once saw a video of a man atop a train touching a naked electric wire and getting burned instantaneously. What’s so special about these little birds anyways?

Why Don’t Birds Get Electrocuted on Electric Wires?

I googled this one and it was pretty easy to find out. The answer as suggested here, is two fold.

• Birds are bad conductors: A bird is made up of cells and tissues, while an electrical wire is made up of metal (mostlly copper). Obviously, a metal is a better conductor and doesn’t provide much resistance to the flow of current. A bird however, is not that good of a conductor. Electricity choses the path of least resistance and flows through the wire ignoring the bird.
• Absence of a Voltage difference: For current to flow through something, it should have a source and a sink i.e., an end with a relatively high voltage and the other end at relatively low voltage. When a bird is perched on a single wire, there is no voltage difference across its different feet, thus, no flow of electricity.

Now that you know the secret to the birds perch, you can easily guess that even humans won’t get electrocuted if they hang from a single wire without touching anything else. Think you can do that?

However, there can be situations where even a bird might get shocked or electrocuted. One such case is when the bird is sitting on a wire and at the same time touching something metallic that touches the ground. In fact, one of the reasons people are advised to wear thick rubber gloves and shoes while working with electric items is to prevent them from acting as a good conductor.

Thinking back, the person in the video got electrocuted. The reason can be that he was standing on a train (a huge, grounded metallic box). I would one day really like to do this experiment of touching a naked wire while hanging in the sky though.