displacement/velocity?

Question

I have a couple of math problems that I believe are interrelated with physics, and I'm not really sure how to solve these problems.

A person drops a ball onto the dirt below. Use this position function to solve the problem: -16t^2 + (initial velocity)(time) + initial height

How high is the wall if the ball hits the dirt 3 seconds after the ball is dropped?

What's the velocity of the ball when it hits the ground?

Thank you very much for your help. I will give 10 points to the most correct answer.

Answer 1

Since the ball was dropped
0=h-16*t^2
and t=3 so
h=16*9 feet
144 ft

velocity is
vy=-32*t
=-32*3
-96 ft/s

j

Answer 2

Displacement, speed, acceleration are vector parts, that's they have instructions. Any of them that's interior the choice direction with admire to the axis of reference would be measured negatively. as an occasion, if a unfastened falling merchandise is launched from relax, for the duration of its action the displacement, the fee and the acceleration are all adverse with admire to a vertical axis pointing upward. If on the choice we opt for the downward direction to be valuable, then the displacement, the fee, the acceleration would be valuable.