Answer :
From the calculation, we can see that the electrostatic force on the material is 1200 N.
What is electrostatic force?
The electrostatic force is described by Coulumb's law. According to the law;
F = Kq1q2/r^2
Where;
q1 = -4 * 10^-3 C
q2 = -3 * 10^-3 C
r = 3 m
K = 9 * 10^9
Hence
F = 9 * 10^9 * -4 * 10^-3 C * -3 * 10^-3 C/(3)^2
F = 1200 N
Learn more about coulumbs law:https://brainly.com/question/23942857
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