Edexcel M2 2013 January — Question 6

Exam BoardEdexcel
ModuleM2 (Mechanics 2)
Year2013
SessionJanuary
TopicProjectiles

6. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{ad18c22c-2fc5-4844-99b8-492f758bb24e-11_531_931_230_520} \captionsetup{labelformat=empty} \caption{Figure 2}
\end{figure} A ball is thrown from a point \(O\), which is 6 m above horizontal ground. The ball is projected with speed \(u \mathrm {~m} \mathrm {~s} ^ { - 1 }\) at an angle \(\theta\) above the horizontal. There is a thin vertical post which is 4 m high and 8 m horizontally away from the vertical through \(O\), as shown in Figure 2. The ball passes just above the top of the post 2 s after projection. The ball is modelled as a particle.
  1. Show that \(\tan \theta = 2.2\)
  2. Find the value of \(u\). The ball hits the ground \(T\) seconds after projection.
  3. Find the value of \(T\). Immediately before the ball hits the ground the direction of motion of the ball makes an angle \(\alpha\) with the horizontal.
  4. Find \(\alpha\).