Hi, I didn't post this question in the Homework section as it is not home work and does not seem to fit with the template. I was wondering if someone could help me out with trying to calculate certain unknowns when computing the trajectory of a mortar round. I think the solution to the problem involves some sort of re-arrangement of the kinematic equations required to solve trajectory problems where you are provided with an initial velocity and an angle. I figure that when trying to hit a target with a mortar. You already know the distance the projectile is required to travel and you also know the force applied to the projectile to cause it to travel. I need to compute the angle that is required in order to make the round land in the right place. I have attempted to work backwards from examples which provide you with an angle and a force and require you to compute the landing point and max height etc, but I have found that I can not find the Time variable required?? Can someone help me out, maybe I am not using the correct equation for this. Any help would be appreciated, thanks.