Edexcel M1 2007 January — Question 4 10 marks

Exam BoardEdexcel
ModuleM1 (Mechanics 1)
Year2007
SessionJanuary
Marks10
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicMomentum and Collisions
TypeDirect collision, find impulse magnitude
DifficultyModerate -0.8 This is a straightforward M1 momentum question requiring direct application of conservation of momentum (with clear before/after states), impulse-momentum theorem, and Newton's second law. All parts follow standard textbook procedures with no problem-solving insight needed—just careful substitution into familiar formulas with attention to sign conventions.
Spec3.03c Newton's second law: F=ma one dimension6.03b Conservation of momentum: 1D two particles6.03e Impulse: by a force6.03f Impulse-momentum: relation

A particle \(P\) of mass 0.3 kg is moving with speed \(u\) m s\(^{-1}\) in a straight line on a smooth horizontal table. The particle \(P\) collides directly with a particle \(Q\) of mass 0.6 kg, which is at rest on the table. Immediately after the particles collide, \(P\) has speed 2 m s\(^{-1}\) and \(Q\) has speed 5 m s\(^{-1}\). The direction of motion of \(P\) is reversed by the collision. Find
  1. the value of \(u\), [4]
  2. the magnitude of the impulse exerted by \(P\) on \(Q\). [2]
Immediately after the collision, a constant force of magnitude \(R\) newtons is applied to \(Q\) in the direction directly opposite to the direction of motion of \(Q\). As a result \(Q\) is brought to rest in 1.5 s.
  1. Find the value of \(R\). [4]

AnswerMarks Guidance
(a) CLM: \(0.3u = 0.3 \times (-2) + 0.6 \times 5\) → \(u = 8\)M1 A1 4 marks
(b) \(I = 0.6 \times 5 = 3\) (Ns)M1 A1 2 marks
(c) \(v = u + at ⇒ 5 = a \times 1.5\) (\(a = \frac{10}{3}\))M1 A1 N2L: \(R = 0.6 \times \frac{10}{3} = 2\)
**(a)** CLM: $0.3u = 0.3 \times (-2) + 0.6 \times 5$ → $u = 8$ | M1 A1 | 4 marks

**(b)** $I = 0.6 \times 5 = 3$ (Ns) | M1 A1 | 2 marks

**(c)** $v = u + at ⇒ 5 = a \times 1.5$ ($a = \frac{10}{3}$) | M1 A1 | N2L: $R = 0.6 \times \frac{10}{3} = 2$ | M1 A1 | 4 marks | 10 marks total

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A particle $P$ of mass 0.3 kg is moving with speed $u$ m s$^{-1}$ in a straight line on a smooth horizontal table. The particle $P$ collides directly with a particle $Q$ of mass 0.6 kg, which is at rest on the table. Immediately after the particles collide, $P$ has speed 2 m s$^{-1}$ and $Q$ has speed 5 m s$^{-1}$. The direction of motion of $P$ is reversed by the collision. Find

\begin{enumerate}[label=(\alph*)]
\item the value of $u$, [4]
\item the magnitude of the impulse exerted by $P$ on $Q$. [2]
\end{enumerate}

Immediately after the collision, a constant force of magnitude $R$ newtons is applied to $Q$ in the direction directly opposite to the direction of motion of $Q$. As a result $Q$ is brought to rest in 1.5 s.

\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{2}
\item Find the value of $R$. [4]
\end{enumerate}

\hfill \mbox{\textit{Edexcel M1 2007 Q4 [10]}}