Acceleration due to gravity in Projectile motions (1 Viewer)

[airie]

What's "when the point of launch is above ground level?"

ie. When the object ends up being lower than its starting point, vertically. The object doesn't have to end up on the ground, actually

and "Find the position of the object and its instantaneous velocity at a given time?" ? How do you find them? I haven't seen any questions related to them... yet.

Basically use the delta(y)=u_yt+0.5a_yt² and delta(x)=u_yt for the positions, and use v²=u²+2ar in both the horizontal and vertical directions (well, but really, v_x would be just the same as u_x), then use Pythagoras to find the overall velocity, and trig (just tan, really) for the angle it makes with the horizontal.

EDIT: 800th post! XD