Question

Two identical copper spheres are separated by 1m in vacuum how many electrons would have to be removed from one spear and added to other so that there now attract each other with a force of 0.9 Newton

Answer 1

Answer:

$F = KQ_{1} Q_{2} /r^{2}$

since K = 9 * 10^-9

so, Q = $10 ^{-4}$