| Exam Board | Edexcel |
|---|---|
| Module | M1 (Mechanics 1) |
| Marks | 6 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Momentum and Collisions |
| Type | Rebound from wall or barrier |
| Difficulty | Moderate -0.8 This is a straightforward application of the impulse-momentum theorem (impulse = change in momentum) with clear given values. The main challenge is correctly handling the sign convention for velocities in opposite directions, but this is a standard M1 technique. Part (b) requires stating common modelling assumptions (uniform ball, rigid wall, etc.) which is routine recall. Significantly easier than average A-level questions as it's a single-concept, direct substitution problem with minimal problem-solving required. |
| Spec | 6.03e Impulse: by a force6.03f Impulse-momentum: relation |
| Answer | Marks | Guidance |
|---|---|---|
| (a) Impulse = change in momentum: \(12 = 25m - (-15m)\) | M1 A1 | |
| \(40m = 12\), \(m = 0.3\) | ||
| (b) Ball = particle, wall vertical | M1 A1; B1 B1 | 6 marks |
**(a)** Impulse = change in momentum: $12 = 25m - (-15m)$ | M1 A1 |
$40m = 12$, $m = 0.3$ | |
**(b)** Ball = particle, wall vertical | M1 A1; B1 B1 | 6 marks |A tennis ball, moving horizontally, hits a wall at $25 \text{ ms}^{-1}$ and rebounds along the same straight line at $15 \text{ ms}^{-1}$. The impulse exerted by the wall on the ball has magnitude $12$ Ns.
\begin{enumerate}[label=(\alph*)]
\item Calculate the mass of the ball. [4 marks]
\item State any modelling assumptions that you have made. [2 marks]
\end{enumerate}
\hfill \mbox{\textit{Edexcel M1 Q1 [6]}}