Question

If you were to drop a rock from a tall building, assuming that it had not yet hit the ground, and neglecting air resistance. What is its vertical displacement (in m) after 6 s? (g = 10 m/s2)

Answer 1

Let us assume the downwards direction as positive.

Gravitational acceleration = g = 10 m/s²

Initial velocity of the rock = V = 0 m/s

Vertical displacement of the rock after 6 sec = H

Time period = T = 6 sec

H = VT + gT²/2

H = (0)(6) + (10)(6)²/2

H = 180 m

The displacement is positive therefore it is directed downwards.

Vertical displacement of the rock after 6 sec = 180 m downwards