Question

A ball is kicked from the top of a building with a velocity of 50 m/s and lands 165 m away from the base of the building.
a) How much time does it take for the ball to hit the ground?

Answer 1

Answer:

3.1 s

Explanation:

we can assume that this motion has a horizontal projectile motion.

projectile motion happens when  an object is subjected to only gravity. Gravity acts to influence the vertical motion of the projectile, it makes a  vertical acceleration.  

The horizontal motion of the projectile is the result of the constant velocity of the object.We assume no acceleration in the horizontal direction.  

applying motion equations

where

s - distance

u - initial velocity

a-acceleration

t - time

s = ut + (1/2)at²

→ 165 = 50t + 0 (as no acceleration is in horizontal direction)

t = 3.1 s