Circular motion help !!! Hello , Here's my question : A pendulum bob has mass 0.2kg. It is attached to one end of a light rod of length 2m. The rod is free to rotate in a vertical plane about an axis through theo ther end o. Given that the pendulum swings through 60degrees on either side of the vertical a.) calculate the speed of the bob at the lowest point of its path b.)the tension in the rod when the rod makes an angle of 30 degrees with the downward vertical For part a.) Using the work-energy principle : v(square) = 2g therefore v = 4.43m/s I have no idea how to do part B My first attempt for this : Using work-energy principle (slotting r=2 , m =0.2 , theta=30,u=0) to find the velocity at that position , so that I can find the tension using Tsin30 - 2g = m.v(square)/r but i just can't get it =( , could anyone help me with tension equations ?