Ask Dr. Universe: Unsafe power lines are not for the birds

Washington State University

Dr. Universe: Why don’t birds get electrocuted when they sit on power lines? – Angel, 14, California

Dear Angel,

I’ve never sat on a power line. I like to stay firmly on the ground. But birds love resting there, especially in winter. Power lines give off a little heat, so it’s a good spot for birds to snuggle together and stay warm.

I talked about how they do that safely with my friend Javier Guerrero. He’s a professor of electrical and computer engineering at Washington State University.

He told me birds do get electrocuted on power lines sometimes. But that won’t happen if the bird touches just the power line – and doesn’t touch other lines or the pole at the same time.

Power lines carry electricity. To understand how this works, we have to talk about atoms. Everything in the world is made of atoms. The air, the water, the bird sitting on the power line. Even you and me. Atoms are the basic building blocks for everything.

Atoms are made of three kinds of particles: protons, neutrons and electrons. The protons and neutrons stick together in the middle of the atom. The electrons float around the outside of the atom. Electrons closer to the middle stick to the atom. But electrons farther away aren’t as stuck. They can be pulled off.

Power plants use magnets to pull off electrons and send them through power lines. They flow