Tennis Ball Cannon -- height of ascent?

This shouldn't be in the tennis section. We're tennis players not rocket scientists

H = Vi * t -(1/2) g t^2 ***(-) since it is going up Note that if we graph H for vertical values and t for horizontal values the tangent at any given time = H/t which defines velocity at any given time in the motion so if we take the first derivative of our equation we get dH/dt = Vi - 2(1/2) g t ****this is our formula for velocity at any given time Note that by the time gravity consumes the momentum of the initial velocity the ball start to free fall. That means it has reach its maximum where the slope is 0 and so is our velocity. Therefore if we plug in a value of 0 for our velocity, we can then compute the time when the ball stops rising and before it starts falling 0 = Vi - g t^2 0 = 40 - 10 t^2 t = (40/10) t = 4 Plug it back into the H equation H = (40)(4) - (1/2)(10)(4^2) H = 160 - 80 H = 80 m *****ANSWER

Haha I am sorry but I have to agree with the guy above me.

Whoah, you're smart :) I can do tennis, and maths, and biology but i suck at physics :)