1. The problem statement, all variables and given/known data A student standing on the ground throws a ball straight up. The ball leaves the studen'ts hand with a speed of 15 m/s when the hand is 2.0m above the ground. How long is the ball in the air before it hits the ground? 2. Relevant equations I'm not sure 3. The attempt at a solution Ok so I'm guessing I have to imply gravity will have an effect on the ball, i'm just not sure how it comes in the equation with the speed. and since there are no forces working on the x axis there should be no mention of range. I also checked on the hyper phisics site under free fall but the only relevant topic gives me this equation: Vy=Voy-gt, but that doesn't quite work for me since I can't clear it for t which is the variable I'm looking for. I need help.