Question

A football is kicked at ground level with a speed of 18.6 m/s at an angle of 44.9 to the horizontal.

How much later does it hit the ground ?

Answer 1

t = 3.79 s

Step-by-step explanation:

We have,

A football is kicked at ground level with a speed of 18.6 m/s at an angle of 44.9 to the horizontal.

It means that,

Initial speed of a football, u = 18.6 m/s

Final speed of a football, v = 0 (when it hits the ground)

It would under the action of gravity. Let t is the time of motion. So, using equation of kinematics to find it.

v=u+at

a=-g

`t=(v-u)/(a)\\\\t=(0-18.6)/(-9.8)\\\\t=1.89\ s`

The total time before the ball hits the ground is the sum of time taken to come down and time taken to go up. So, total time is 2×1.89 = 3.79 s