Question

The height of a helicopter above the ground is given by h = 2.80t³, where h is in meters and t is in seconds. At t = 1.90 s, the helicopter releases a small mailbag.
(a) How long after its release does the mailbag reach the ground?  
(b) With what velocity does the mailbag hit the ground?

Answer 1

The height of the helicopter is given by

At time t = 1.9seconds,

The height of the helicopter will be

A)

The mailbox need to move this height before it hits the ground.

Using eqn of motion,

B)

Ghe velocity with which the box hits the ground can be obtained by the formula