I have the initial X and Y velocity of a ping pong ball that was launched from a mechanical device at angle Theta (45 degrees). X_i = 3.378 m/s, Y_i = 2.027 m/s. I have a series of frames I've captured with a video capture program, which I pointed at the ping pong ball and the software calculated the X and Y position for that frame. I need to calculate the theoretical Y position for each frame using some formula.... Which formula would accomplish this?