A ball is thrown vertically upward at 10 m/s from the edge of a building that is 50 m high. How long does it take the ball to reach the ground?
1 Answer
It takes about 4.37 seconds.
Explanation:
To solve this we'll break the time down into two parts.
with
First we'll solve for
Then we'll solve for t_2 using the distance formula (note here that the velocity when the ball is heading down from the height of the tower is going to be 10 m/s toward the ground).
When solved, this polynomial equation yields either:
or
Only the positive one corresponds to a real physical possibility so we'll use that and solve.