A system of three charges are placed as shown in the figure :

If D >> d, the potential energy of the system is best given by :

Determine the charge on the capacitor in the following circuit :

A simple pendulum oscillating in air has period T. The bob of the pendulum is completely immersed in a non-viscous liquid. The density of the liquid is 1/16 th of the material of the bob. If the bob is inside liquid all the time, its period of oscillation in this liquid is :

Following figure shows two processes A and B for a gas. If $$\Delta $$Q_A and $$\Delta $$Q_B are the amount of heat absorbed by the system in two cases, and $$\Delta $$U_A and $$\Delta $$U_B are changes in internal energies, respectively, then :