OCR M1 2010 June — Question 2 9 marks

Exam BoardOCR
ModuleM1 (Mechanics 1)
Year2010
SessionJune
Marks9
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicMomentum and Collisions
TypeCollision with two possible outcomes
DifficultyModerate -0.3 This is a straightforward momentum conservation problem with two scenarios. Part (i) requires a single application of conservation of momentum with clear direction. Part (ii) adds a simple kinematics step (distance = speed × time) after another momentum calculation. The question is slightly easier than average because it's a standard textbook exercise with no conceptual challenges—students just need to apply the momentum formula carefully with signs, which is routine M1 content.
Spec6.03b Conservation of momentum: 1D two particles

2 Two particles \(P\) and \(Q\) are moving in opposite directions in the same straight line on a smooth horizontal surface when they collide. \(P\) has mass 0.4 kg and speed \(3 \mathrm {~m} \mathrm {~s} ^ { - 1 } . Q\) has mass 0.6 kg and speed \(1.5 \mathrm {~m} \mathrm {~s} ^ { - 1 }\). Immediately after the collision, the speed of \(P\) is \(0.1 \mathrm {~m} \mathrm {~s} ^ { - 1 }\).
  1. Given that \(P\) and \(Q\) are moving in the same direction after the collision, find the speed of \(Q\).
  2. Given instead that \(P\) and \(Q\) are moving in opposite directions after the collision, find the distance between them 3 s after the collision.

2 Two particles $P$ and $Q$ are moving in opposite directions in the same straight line on a smooth horizontal surface when they collide. $P$ has mass 0.4 kg and speed $3 \mathrm {~m} \mathrm {~s} ^ { - 1 } . Q$ has mass 0.6 kg and speed $1.5 \mathrm {~m} \mathrm {~s} ^ { - 1 }$. Immediately after the collision, the speed of $P$ is $0.1 \mathrm {~m} \mathrm {~s} ^ { - 1 }$.\\
(i) Given that $P$ and $Q$ are moving in the same direction after the collision, find the speed of $Q$.\\
(ii) Given instead that $P$ and $Q$ are moving in opposite directions after the collision, find the distance between them 3 s after the collision.

\hfill \mbox{\textit{OCR M1 2010 Q2 [9]}}