a stone is projected upward with a speed of 80.0ft/s from a 224 ft tower. find the maximum height and the speed at which it strikes the ground.

1 answer

Assuming no air resistance, and PE at bottom of tower to be zero, then
At the maximum height,
mgh=(224mg+m(80²)/2
h=224+80²/(2g) [assume g=32.2 '/s²
=224'+99.38'
=323.38'

At bottom of tower,
mv²/2 = m(80²)/2+mg(224)
solve for v to get
v=144.31 '/s