Question

A rock is thrown vertically upward from ground level at time t = 0. At t = 1.8 s it passes the top of a tall tower, and 1.0 s later it reaches its maximum height. What is the height of the tower?

Answer 1

33.5 m

Step-by-step explanation:

Ignore air resistance and assume g = 9.8 m/s²

Falling down, it follows the reverse path.

From the ape x, it dropped ½(9.8)1.0² = 4.9 m to the top of the tower.

From the ape x, it dropped ½(9.8)(1.0 + 1.8)² = 38.4 m to the ground.

The tower is 38.4 - 4.9 = 33.5 m tall.