Question

can anyone solve this class 12 numerical

Answer 1

Let Q1 = 2 * $10^{-7}$ C
Q2 = 3 * $10^{-7}$ C
Distance between them is d = 30 * $10^{-2}$ m

Force between two spherical charges is given by:
F = (1/4πε₀) [ Q1*Q2 ]  /  $d^{2}$ 

F = 9* $10^{9}$ * 2 * $10^{-7}$ * 3 * $10^{-7}$  / ( 30 * $10^{-2}$ )²

F = 6 * $10^{-3}$  N


F = 0.006 N which is the required answer.