Two charged balls of same radius and weight suspended on threads of equal length from the same point are in equilibrium with their threads making certain angle (system is in air). Now the system is immersed in liquid of density \(d\) and dielectric constant \(K\), again equilibrium is reestablished. Find the density of the balls so that the angle of divergence of the thread is same for both medium.
Details and Assumptions
\(K=10, d= 9 \).
All values are in SI units, Calculate answer in SI units.