A ball is thrown down at 72 km h–1 speed from the top of a building. The
building is 125 metres tall. The distance travelled before it reach the
ground is as follows,
s = u0t + 1/2gtsquared
where:
u0 = initial velocity (ms -1)
g = acceleration due to gravity (10 ms -2)
t = time (s)
Find the time for the ball to drop to fifth of the height of the building.
&
Find the time for the ball to reach the ground.
That's not at all what I get. Could you show your calculations?
(Of course, the quadratic equation will have two roots but the ball is not likely to hit the ground before it was thrown upward, is it?)