A ball is thrown vertically upward from a cliff with a speed of 20 ft/sec. The ball hits the ground at 140 ft/sec. How high is the cliff?
v'+-32
If in feet it is math not physics so here g = 32 ft/s^2
v = Vi + a t
a = -32
so
140 = 20 - 32 t
t = 3.75 seconds
h = Hi + Vi t - 16 t^2
0 = Hi + 20 (3.75) - 16 (3.75)^2
solve for Hi