Edexcel M2 — Question 6

Exam BoardEdexcel
ModuleM2 (Mechanics 2)
TopicProjectiles

6. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{f5449ec3-ead0-464f-9d03-f225cd21bca6-4_412_770_198_507} \captionsetup{labelformat=empty} \caption{Fig. 2}
\end{figure} A football player strikes a ball giving it an initial speed of \(14 \mathrm {~ms} ^ { - 1 }\) at an angle \(\alpha\) to the horizontal as shown in Figure 2. At the instant he strikes the ball it is 0.6 m vertically above the point \(P\) on the ground. The trajectory of the ball is in a vertical plane containing \(P\) and \(M\), the middle of the goal-line. The distance between \(P\) and \(M\) is 12 m and the ground is horizontal. Given that the ball passes over the point \(M\) without bouncing,
  1. find, to the nearest degree, the minimum value of \(\alpha\). Given that the crossbar of the goal is 2.4 m above \(M\) and that \(\tan \alpha = \frac { 4 } { 3 }\),
  2. show that the ball passes 4.2 m vertically above the crossbar.