Question

A ball Is thrown horizontally from the top of a 20m high cliff. If the velocity is 8m/s. Calculate;
1. How long it takes the ball to reach the horizontal plane at the foot

Answer 1

Given that the ball is thrown horizontally, we know that its initial vertical velocity is zero. The only force acting on the ball in the vertical direction is gravity, causing it to accelerate downwards at a rate of 9.8 m/s².

Using the kinematic equation:
s = ut + (1/2)at²
where s is the distance traveled, u is the initial velocity, t is the time, and a is the acceleration,

We can apply this equation to the vertical motion of the ball from the top of the cliff to the ground:
20m = 0 + (1/2)(9.8m/s²)t²

Simplifying the equation:
10t² = 20
t² = 2
t = √2

Therefore, it takes the ball √2 seconds to reach the horizontal plane at the foot of the cliff.