| Exam Board | AQA |
|---|---|
| Module | M1 (Mechanics 1) |
| Year | 2012 |
| Session | January |
| Marks | 9 |
| Paper | Download PDF ↗ |
| Topic | Newton's laws and connected particles |
| Type | Block on rough horizontal surface – accelerating (finding acceleration or applied force) |
| Difficulty | Moderate -0.8 This is a straightforward M1 mechanics question testing basic application of Newton's second law and friction concepts. Parts (a)-(d) are routine calculations requiring standard force diagrams and F=ma with no problem-solving insight needed. Part (e) adds minimal complexity with a conceptual explanation. Easier than average A-level due to its step-by-step scaffolding and standard textbook format. |
| Spec | 3.03c Newton's second law: F=ma one dimension3.03d Newton's second law: 2D vectors3.03i Normal reaction force3.03t Coefficient of friction: F <= mu*R model |
2 A block, of mass 4 kg , is made to move in a straight line on a rough horizontal surface by a horizontal force of 50 newtons, as shown in the diagram.\\
\includegraphics[max width=\textwidth, alt={}, center]{d42b2e88-74ea-486b-bb47-f512eb0c185d-2_113_1075_913_486}
Assume that there is no air resistance acting on the block.
\begin{enumerate}[label=(\alph*)]
\item Draw a diagram to show all the forces acting on the block.
\item Find the magnitude of the normal reaction force acting on the block.
\item The acceleration of the block is $3 \mathrm {~m} \mathrm {~s} ^ { - 2 }$. Find the magnitude of the friction force acting on the block.
\item Find the coefficient of friction between the block and the surface.
\item Explain how and why your answer to part (d) would change if you assumed that air resistance did act on the block.
\end{enumerate}
\hfill \mbox{\textit{AQA M1 2012 Q2 [9]}}