Question

The earth has an electric field pointing radially down that averages 100 N/C. Thisfield is maintained by atmospheric processes, including lightning. What is the excesscharge on the surface of the earth ?

Answer 1

Step-by-step explanation:

Given

Average Electric Field Strength
`E=100\ N/C`

Considering charge distribution to be uniform and earth to be symmetrical

Using Gauss law

`\phi =\oint \vec{E}\cdot \vec{dA}`

`\phi =E\cdot A_(sphere)`

Also
`E\cdot A_(sphere)=(Q_(inside))/(\epsilon )`

here Electric Field is acting inward therefore

`Q=-\epsilon EA_(sphere)`

`Q=-8.85* 10^(-12)* 100* 4\pi * (6.37* 10^6)^2`

`Q=-4.51* 10^5\ C`