Question

A stone is dropped from the upper observation deck of a tower, 900 m above the ground. (assume g = 9.8 m/s2.) (a) find the distance (in meters) of the stone above ground level at time t. h(t) = 900â9.8t2

Answer 1

The original vertical velocity = 0 (because the stone was dropped).
Assume that air resistance may be ignored.

Let x = the distance the stone drops in time t.
Then
x = 0*t + (1/2)*(9.8 m/s²)*(t s)²
   = 4.9t² m

The height of the stone above ground is
h(t) = 900 - 4.9t² m

Answer: h(t) = 900 - 4.9t²