Question

two isolated charged metallic spheres of radii r1 and r2 having charges q1 and q2 respectively are connected to each other, then there is a decrease in energy of the system until q1R2 = q2R1.
Explain ts statement.

Answer 1

=> Two isolated metallic spheres of radii $R_1 ,R_2$ having charges $Q_1 ,Q_2$ respectively are brought in contact with each other.

=> Charges will flow across the point of contact from where they are connected until their potential at their surfaces became same.
Energy is decreased cause system changes to get stability.

=> Potential at their surfaces are same :
$V_1 = V_2 \\ =>\frac{KQ_1}{R_1 }= \frac{KQ_2}{R_2} \\ => \red{Q_1 R_2 = Q_2 R_1}$
Hence Proved