| Exam Board | Edexcel |
|---|---|
| Module | M1 (Mechanics 1) |
| Year | 2008 |
| Session | June |
| Marks | 6 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Momentum and Collisions |
| Type | Given impulse, find velocity or mass |
| Difficulty | Easy -1.2 This is a straightforward two-part mechanics question requiring only direct application of impulse-momentum theorem (impulse = change in momentum) and conservation of momentum. Part (a) is a single-step calculation, and part (b) is a simple 'show that' verification using conservation of momentum with given values. No problem-solving insight or multi-step reasoning required. |
| Spec | 6.03b Conservation of momentum: 1D two particles6.03c Momentum in 2D: vector form6.03f Impulse-momentum: relation6.03g Impulse in 2D: vector form |
| Answer | Marks | Guidance |
|---|---|---|
| (a) \(I = mv \Rightarrow 3 = 0.4 \times v\) giving \(v = 7.5 \text{ (ms}^{-1})\) | M1 A1 | (3) |
| (b) \(0.4 \times 7.5 = 0.4v + 0.6 \times 5\) leading to \(0 = 0.4v \Rightarrow v = 0\) | M1 A1 cso | A1 (3) [6] |
**(a)** $I = mv \Rightarrow 3 = 0.4 \times v$ giving $v = 7.5 \text{ (ms}^{-1})$ | M1 A1 | (3)
**(b)** $0.4 \times 7.5 = 0.4v + 0.6 \times 5$ leading to $0 = 0.4v \Rightarrow v = 0$ | M1 A1 cso | A1 (3) [6]
---\begin{enumerate}
\item Two particles $P$ and $Q$ have mass 0.4 kg and 0.6 kg respectively. The particles are initially at rest on a smooth horizontal table. Particle $P$ is given an impulse of magnitude 3 N s in the direction $P Q$.\\
(a) Find the speed of $P$ immediately before it collides with $Q$.
\end{enumerate}
Immediately after the collision between $P$ and $Q$, the speed of $Q$ is $5 \mathrm {~m} \mathrm {~s} ^ { - 1 }$.\\
(b) Show that immediately after the collision $P$ is at rest.\\
\hfill \mbox{\textit{Edexcel M1 2008 Q1 [6]}}