| Exam Board | Edexcel |
|---|---|
| Module | M2 (Mechanics 2) |
| Marks | 7 |
| Paper | Download PDF ↗ |
| Topic | Centre of Mass 1 |
| Type | Particles at coordinate positions |
| Difficulty | Moderate -0.8 This is a straightforward application of the centre of mass formula with clearly given masses and coordinates. Part (a) is a 'show that' requiring substitution into the x-coordinate formula, and part (b) is identical calculation for the y-coordinate. Both parts involve only arithmetic with no conceptual challenges or problem-solving—purely routine mechanics bookwork that's easier than average A-level questions. |
| Spec | 6.04b Find centre of mass: using symmetry |
Three particles of mass $3m$, $5m$ and $2m$ are placed at points with coordinates $(4, 0)$, $(0, -3)$ and $(4, 2)$ respectively. The centre of mass of the system of three particles is at $(2, k)$.
\begin{enumerate}[label=(\alph*)]
\item Show that $λ = 2$.
[4]
\end{enumerate}
\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{1}
\item Calculate the value of $k$.
[3]
\end{enumerate}
\hfill \mbox{\textit{Edexcel M2 Q1 [7]}}