(a) Two identical spheres having positive charges are placed `3 m` apart repel each other with a force `8 xx 10^(-3) N`. Now charges are connected by a metallic wire, they begin to repel each other with a force of `9 xx 10^(-3) N`. Find initial charges on the spheres.
(b) Two identical spheres having charges of opposite sign are placed `3 m` apart attract other with a force `2.4 xx 10^(-3) N`. Now spheres are touched and then placed at original separation repel with a force `10^(-3) N`. Find initial charges on the spheres.

Explanation

To solve the given problem, we will use Coulomb's Law, which states that the force \( F \) between two point charges \( q_1 \) and \( q_2 \) separated by a distance \( r \) is given by:

\[ F = k \frac{|q_1 q_2|}{r^2} \]

where \( k \) is Coulomb's constant, approximately \( 8.99 \times 10^9 \, \text{N m}^2/\text{C}^2 \).

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