# What is hang time?

by ThetaPi
Tags: time
 P: 9 Could someone kindly explain to me what hang time is, in the context of 2D projectile motion? Enlighten me on the equations of motion that might be applicable to such a problem. In other words, given a projectile launched at $$\theta$$ above the horizontal with an initial velocity of $$v_0$$, how do we calculate the hang time? Thoughts. We need to calculate the time it takes for the projectile to reach the maximum height of the trajectory ($$t_1$$), and the time it takes to hit the ground after attaining its maximum height ($$t_2$$), and then add up $$t_1+t_2$$. I think that it will be convenient to use the y-component of $$v_0$$. The maximum height of the trajectory is $$|1/2gt_2^2|$$. We can use this in the equation $$s_y=v_{0y}t_1-1/2gt_1^2$$ to find $$t_1$$. I am rather confused...some posts I saw while browsing the forums said that the initial velocity does not affect the "hang time". Thank you TS