Question
Answer the following:
The top of the atmosphere is at about 400 kV with respect to the surface of the earth, corresponding to an electric field that decreases with altitude. Near the surface of the earth, the field is about 100 V m–1. Why then do we not get an electric shock as we step out of our house into the open? (Assume the house to be a steel cage so there is no field inside!)
Solution
The surface of the earth and our body both are good conductors. Therefore, our body and the surface of the ground form an equipotential surface. And, the original equipotential surface of open air changes or modifies as we step out of the house, into the open. Hence, our body and the ground is kept at the same potential. Therefore, we do not get an electric shock.
