1. The problem statement, all variables and given/known data A pendulum 2.00m long is released (from rest) at an angle (theta) = 30 degrees. Determine the speed of the 70.0g bob: (a) at the lowest point (theta = 0 degrees), and (b) at (theta) = 15 degrees. 2. Relevant equations I really don't even know where to begin with this one. 3. The attempt at a solution See above. I'm going to need a lot of help. I think I first need to find the potential energy of the bob when it is at 30 degrees, using the equation u=mgy, but I don't know how to find the y component. I think I then need to take that value of potential energy and set it equal to 1/2mv^2 to find the velocity at (theta) = 0 degrees. Then I think I need to do those same calculations, except subsituting 15 degrees instead of 30 degrees when finding potential energy. So how would I go about finding the y component?