Two small spherical balls each carrying a charge Q = 10 μC are suspended by two insulating threads of equal lengths 1 m each, from a point fixed in the ceiling. It is found that in equilibrium threads are separated by an angle 60° between them, as shown in the figure. What is the tension in the threads?$(\mathrm{Given}: \left.\frac{1}{4{\mathrm{\pi \epsilon }}_0}=9\times {10}^9\mathrm{Nm}/{\mathrm{C}}^2\right)$