Physics

Two small spheres spaced 20.0 centimeters apart have equal charge.

How many excess electrons must be present on each sphere if the magnitude of the force of repulsion between them is 4.57×10 −21 newtons?

1. 👍 0
2. 👎 0
3. 👁 197
1. F=k QQ/r^2

solve for q, then dvide by the charge on one electron

1. 👍 0
2. 👎 1

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