A bird can safely land on a bare, high-voltage power line because
A) if both feet are touching the bare wire, they are at approximately the same potential, and therefore little or no current flows through the bird's body.
B) its internal resistance is very high, so very little current will flow.
C) the line cannot deliver enough current to harm it.
D) its feet are good insulators, and therefore it is protected.

Question

Quizplus · Accepted Answer

When both feet of the bird are touching the bare wire, they are at the same potential, and therefore, very little or no current flows through the bird's body. This is known as the principle of equipotentiality. The bird's internal resistance or the amount of current the line can deliver are not as important factors as the principle of equipotentiality. The insulation of the feet is also not a significant factor.

A Bird Can Safely Land on a Bare, High-Voltage Power