Assume that in interstellar space the distance between two electrons is about 0.87 cm. The electric force between them are repulsive. Calculate the electric force between these two electrons. The value of the Coulomb constant 9 × 109 N · m2/C2 and the elemental charge is 1.6 × 10−19 C.

Part 2. Calculate the gravitational force between these two electrons. The universal gravitational constant is 6.7 × 10−11 N · m2/kg2 and the mass of the electron is 9 × 10−31 kg.

3 answers

Electric force:
ke^2/R^2

1. Use R = 0.0087 meters
k = 9*10^9 N·m^2/C^2
e = 1.6*10^-19 C
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2. Gravitational force:
G*m^2/R^2
G = 6.7×10−^11 N·m^2/kg^2
m = 9.1*10^31 kg
Use same R as abOve

2.56e-21

1.9e-5