Question

A football kicker is attempting a field goal from 44m out. The ball is kicked and just clears the lower bar with a time of flight of 2.9s. If the angle of the kick was 45°, what was the initial speed of the ball, assuming no air resistance?Group of answer choices

Answer 1

Given,

Distance travelled, d=44 m.

The time of flight t=2.9 s

The angle is

`\theta=45^o`

Let the initial velocity be v

The motion is projectile.

Thus the horizontal distance travelled is

`\begin{gathered} d=(v\cos \theta)t \\ \Rightarrow44=v*\cos 45^o*2.9 \\ \Rightarrow v=21.5\text{ m/s} \end{gathered}`

Thus the answer is 21.5 m/s