| Exam Board | Edexcel |
|---|---|
| Module | M2 (Mechanics 2) |
| Marks | 16 |
| Paper | Download PDF ↗ |
| Topic | Momentum and Collisions 1 |
| Type | Range of coefficient of restitution |
| Difficulty | Standard +0.3 This is a standard M2 collision question requiring conservation of momentum and Newton's restitution law. Part (a) is routine 'show that' with given answer, part (b) is immediate follow-up, and part (c) requires setting up inequalities for no further collisions—all standard techniques for this module with no novel insight needed. Slightly easier than average due to the scaffolded structure and 'show that' guidance. |
| Spec | 6.03b Conservation of momentum: 1D two particles6.03k Newton's experimental law: direct impact |
A particle $A$ of mass $2m$ is moving with speed $2u$ on a smooth horizontal table. The particle collides directly with a particle $B$ of mass $4m$ moving with speed $u$ in the same direction as $A$. The coefficient of restitution between $A$ and $B$ is $\frac{1}{2}$.
\begin{enumerate}[label=(\alph*)]
\item Show that the speed of $B$ after the collision is $\frac{3}{2}u$.
[6]
\end{enumerate}
\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{1}
\item Find the speed of $A$ after the collision.
[2]
\end{enumerate}
Subsequently $B$ collides directly with a particle $C$ of mass $m$ which is at rest on the table. The coefficient of restitution between $B$ and $C$ is $e$. Given that there are no further collisions,
\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{2}
\item find the range of possible values for $e$.
[8]
\end{enumerate}
\hfill \mbox{\textit{Edexcel M2 Q6 [16]}}