OCR MEI Paper 1 2018 June — Question 9

Exam BoardOCR MEI
ModulePaper 1 (Paper 1)
Year2018
SessionJune
TopicProjectiles

9 A pebble is thrown horizontally at \(14 \mathrm {~ms} ^ { - 1 }\) from a window which is 5 m above horizontal ground. The pebble goes over a fence 2 m high \(d \mathrm {~m}\) away from the window as shown in Fig. 9. The origin is on the ground directly below the window with the \(x\)-axis horizontal in the direction in which the pebble is thrown and the \(y\)-axis vertically upwards. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{904025c9-6d68-4344-bd41-8c0fccfcf92f-06_538_1082_452_488} \captionsetup{labelformat=empty} \caption{Fig. 9}
\end{figure}
  1. Find the time the pebble takes to reach the ground.
  2. Find the cartesian equation of the trajectory of the pebble.
  3. Find the range of possible values for \(d\).