Question

Problem 86

Answer 1

Given information

Given:

A bolt of lightning strikes a metal flag pole,

The flag pole is anchored in the ground,

The magnetic field of the earth is .

To determine an estimated value of force exerted by the Earth's magnetic field on the flag pole induced with the lightning current.

Step-by-step explanation

Step 1.

In example 18-10, the estimated value of the current in a lightning bolt is ;

The force on an electric current in a magnetic field is given by the expression,

 

But as lightning current is perpendicular to the earth magnetic field, ;