a ball rolls horizontally off a cliff at a speed of 30m/s. it takes about two seconds for the ball to hit the ground. calculate the height of the cliff and the horizontal distance travelled by the ball.

(a) The height of the cliff is 19.6 m

(b) The horizontal distance travelled by the ball is 60 m

Explanation:

Given;

initial horizontal velocity of the ball, u = 30 m/s

initial vertical velocity of the ball, v = 0

time taken for the ball to hit the ground, t = 2 s

(a) height of the cliff

h = vt + ¹/₂gt²

h = 0 + ¹/₂gt²

h = ¹/₂gt²

h = ¹/₂(9.8)(2)²

h = 19.6 m

(b) horizontal distance traveled by the ball = Range

Range = ut

Range = 30 (2)

Range = 60 m

answer: 31, 5556. 952 seconds