Edexcel M2 — Question 7 16 marks

Exam BoardEdexcel
ModuleM2 (Mechanics 2)
Marks16
PaperDownload PDF ↗
TopicProjectiles
TypeProjection from elevated point - angle above horizontal
DifficultyStandard +0.3 This is a standard M2 projectiles question combined with kinematics involving integration. Part (a) uses standard SUVAT equations with projectile motion (5 marks suggests routine calculation). Parts (b-d) involve straightforward integration of acceleration to find velocity and position, then comparing distances. The 'show that' parts guide students to expected answers. While multi-part with 16 total marks, each component uses standard techniques without requiring novel insight or complex problem-solving.
Spec1.08d Evaluate definite integrals: between limits3.02f Non-uniform acceleration: using differentiation and integration3.02i Projectile motion: constant acceleration model

\includegraphics{figure_2} At time \(t = 0\) a small package is projected from a point \(B\) which is \(2.4\) m above a point \(A\) on horizontal ground. The package is projected with speed \(23.75\) m s\(^{-1}\) at an angle \(α\) to the horizontal, where \(\tan α = \frac{4}{5}\). The package strikes the ground at point \(C\), as shown in Fig. 2. The package is modelled as a particle moving freely under gravity.
  1. Find the time taken for the package to reach \(C\). [5]
A lorry moves along the line \(AC\), approaching \(A\) with constant speed 18 m s\(^{-1}\). At time \(t = 0\) the rear of the lorry passes \(A\) and the lorry starts to slow down. It comes to rest 7 seconds later. The acceleration, \(a\) m s\(^{-2}\) of the lorry at time \(t\) seconds is given by $$a = -\frac{1}{4}t^2, \quad 0 \leq t \leq 7.$$
  1. Find the speed of the lorry at time \(t\) seconds. [3]
  1. Hence show that \(T = 6\). [3]
  1. Show that when the package reaches \(C\) it is just under 10 m behind the rear of the moving lorry. [5]
END

\includegraphics{figure_2}

At time $t = 0$ a small package is projected from a point $B$ which is $2.4$ m above a point $A$ on horizontal ground. The package is projected with speed $23.75$ m s$^{-1}$ at an angle $α$ to the horizontal, where $\tan α = \frac{4}{5}$. The package strikes the ground at point $C$, as shown in Fig. 2. The package is modelled as a particle moving freely under gravity.

\begin{enumerate}[label=(\alph*)]
\item Find the time taken for the package to reach $C$.
[5]
\end{enumerate}

A lorry moves along the line $AC$, approaching $A$ with constant speed 18 m s$^{-1}$. At time $t = 0$ the rear of the lorry passes $A$ and the lorry starts to slow down. It comes to rest 7 seconds later. The acceleration, $a$ m s$^{-2}$ of the lorry at time $t$ seconds is given by

$$a = -\frac{1}{4}t^2, \quad 0 \leq t \leq 7.$$

\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{1}
\item Find the speed of the lorry at time $t$ seconds.
[3]
\end{enumerate}

\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{2}
\item Hence show that $T = 6$.
[3]
\end{enumerate}

\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{3}
\item Show that when the package reaches $C$ it is just under 10 m behind the rear of the moving lorry.
[5]
\end{enumerate}

END

\hfill \mbox{\textit{Edexcel M2  Q7 [16]}}