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**1. Homework Statement**

A 2 C charge is spread uniformly in a hollow sphere with a radius of 50 cm.

a) What is the electric flux?

b) What is the magnitude and direction of an electric field 200 cm away?

**2. Homework Equations**

Electric flux = q/(permittivity of free space)

E = q/4(pi)(permittivity of free space)r

^{2}

q = charge

The permittivity of free space = 8.85 x 10

^{-12}C

^{2}/(N*m

^{2})

r = radius

**3. The Attempt at a Solution**

Because the electric flux = the enclosed net charge divided by the permittivity of free space (approx. 8.85 x 10

^{-12}) I attempted to use this equation. Using 2 C as the net charge, I found the answer to be about 2.26 N*m

^{2}/C

I had no idea how to solve the second part of the question, but referenced my book and found this equation:

E = q/4(pi)(permittivity of free space)r

^{2}

q = charge

The permittivity of free space = 8.85 x 10

^{-12}C

^{2}/(N*m

^{2})

r = radius

My problem with this equation is that it doesn't seem to incorporate both the 50 cm and the 200 cm distances that are given within the question, but using 200 cm as the value of r, I calculated the answer to part b as 8.99 x 10

^{9}N/C

Any help would be greatly appreciated!

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