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**1. Homework Statement**

The Earth is surrounded by an electric field, pointing inward at every point. Assume a magnitude of E = 142N/C near the surface.

a) What is the net charge on the Earth?

b) How many excess electrons per square meter on the Earth's surface does this correspond to?

E = 142 N/C

Radius of Earth = 6.3781 km = 6,378,100 m

**2. Homework Equations**

Gauss's Law = EA

**3. The Attempt at a Solution**

So i know that i have to use Gauss's Law here. Which is simple the Electric Field, (given) and the area of the earth which is found be 4πr

^{2}

Gauss's Law = EA

= (142) * (4πr

^{2})

= (142) * (4π(6,378,100)

^{2})

= (142) * (5.11e+14)

= 7.26e+16 C

however. After attempting that, i found it wasn't the right answer. Where did i go wrong?

i haven't attempted the second part since i need to know the first part. But i assume that to do it i would have to find the surface area of the earth and divide it by the number i found in part a, then divide that by 1.6e-19 to find the number of electrons?