A rod of mass m and length l is made to stand at an angle of 60o with the vertical. Potential energy of the rod in this position is?
A rod of mass m and length l is lying on a horizontal table. The work done in making it stand vertically on one end will be
A pendulum is made from a massless rod of length L and bob of mass m. A spring of force constant k is connected horizontally to it at a distance h below its point of suspension as shown. The rod is in equilibrium in vertical position. The frequency of vibration of the system for small values of θ is :