| Exam Board | Edexcel |
|---|---|
| Module | M5 (Mechanics 5) |
| Session | Specimen |
| Marks | 5 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Work done and energy |
| Type | Work done by constant force - vector setup |
| Difficulty | Standard +0.3 This is a straightforward M5 work-energy question requiring calculation of work done using W = F·s (dot product) and then applying the work-energy principle. Both parts use standard formulas with no conceptual challenges—students simply need to find the displacement vector, compute the dot product, and use KE = work done. Slightly above average difficulty only due to 3D vectors, but the method is routine for M5 students. |
| Spec | 1.10g Problem solving with vectors: in geometry6.02b Calculate work: constant force, resolved component6.02i Conservation of energy: mechanical energy principle |
A bead of mass 0.125 kg is threaded on a smooth straight horizontal wire. The bead moves from rest at the point $A$ with position vector $(2\mathbf{i} + \mathbf{j} - \mathbf{k})$ m relative to a fixed origin $O$ to a point with position vector $(3\mathbf{i} - 4\mathbf{j} - \mathbf{k})$ m relative to $O$ under the action of a force $\mathbf{F} = (14\mathbf{i} + 2\mathbf{j} + 3\mathbf{k})$ N. Find
\begin{enumerate}[label=(\alph*)]
\item the work done by $\mathbf{F}$ as the bead moves from $A$ to $B$, [3]
\item the speed of the bead at $B$. [2]
\end{enumerate}
\hfill \mbox{\textit{Edexcel M5 Q1 [5]}}