The force between the two charges will be 16,000 N. It is the force exerted by one charge on another charge.
What is electric force?
The electric force between the two charges is directly proportional to the product of the charge and inversely proportional to the square of the distance between them.
The given data in the problem is;
The magnitude of charge of sphere q₁ = +3.0 μC=-3.0×10⁻⁶ C
The magnitude of charge of sphere q₂ = -9.0 μC=9.0×10⁻⁶ C
k is the proportionality constant = 9 × 10⁹ Nm²
r is the separated distance to be found;
The electric force is F = 0.20 mN = 0.20 ×10⁻³ N
The electric force is found as;
[tex]\rm F = \frac{K q_1q_2}{r^2} \\\\ \rm 0.20 \times 10^{-3} = \frac{9 \times 10^9 \times 3.0 \times 10^{-6}\times 3.0 \times 10^{-6} }{r^2} \\\\\ R^ 2 =4.04\times 10^{-4} \\\\ R= 0.020 \ m[/tex]
Hence, the force between the two charges will be 16,000 N.
To learn more about the electric force, refer to the link;
https://brainly.com/question/1076352
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