Two identical balls made of putty, each of mass 1.50 kg, are suspended from strings of length 28.0 cm so that they touch when in their equilibrium position. We pull one of the balls back until its string makes an angle theta = 73.0 degrees with the vertical and let it go. It collides totally inelastically with the other ball, which means the two balls remain stuck together after the collision. How high will the stuck-together balls rise above the bottom most point? So this is a Completely Inelastic Collision in Two deminsions, right? Do i have all the information I need or do i have to find velocities, I don't know any formulas with theta involved.