Question

Assume that in interstellar space the distance between two electrons is about 0.47 cm. What is the electric force between the two electrons?

Answer 1

4.90867474 `*10^-26`Newton

Explanation:

What is the medium in interstellar space?
It is vacuum obviously. And thus the permittivity is always `epsilon_0` which is equal to 8.854187817`*10^-12` farads per meter.

Now,
Electric force between two electrons, let F;
F =`{1/(4*pi*epsilon_0)*(q^2)/(r^2)}` = `{1/(4*pi*epsilon_0)*(e^2)/(4.7*10^-3)^2}` = 4.90867474 `*10^-23`Newton

As the charges are both negative they keeps the tendency to repel each other.

Answer 2

`1.04 * 10^-23` N

Explanation:

the electric force is given by `(k *q_1*q_2)/r^2`

Here , `q_1 and q_2` are same and equal to `e`
The distance of separation is 0.0047 m and the value of k
is `9*10^9`

So , Electric force = `1.04 * 10^-23` N