Question

From the top of a 490 m high cliff a boy throws a stone horizontally with an initial speed of 15m/s. find the speed with which the stone hits the ground

Answer 1

This is a question on horizontal projection.

The horizontal velocity is constant.

The vertical velocity changes with time.

Given the vertical distance and the initial velocity we will use the following equation of motion to get the final velocity.

V² = U² + 2gs

S = 490

g = 10

U = 15

V² = 225 + 9800

V² = 10025

V = √10025 = 100.12

= 100.12 m/s

Answer 2

Here is your answer.

Hope this helps you.