AQA M2 2011 January — Question 2 5 marks

Exam BoardAQA
ModuleM2 (Mechanics 2)
Year2011
SessionJanuary
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicWork done and energy
TypeEnergy method - smooth inclined plane (no resistance)
DifficultyModerate -0.8 This is a straightforward application of energy conservation on an inclined plane with clear step-by-step guidance ('hence' structure). It requires only standard formulas (PE = mgh, KE = ½mv²) and basic trigonometry to find the height drop, making it easier than average with no problem-solving insight needed.
Spec6.02e Calculate KE and PE: using formulae6.02i Conservation of energy: mechanical energy principle

2 A particle is placed on a smooth plane which is inclined at an angle of \(20 ^ { \circ }\) to the horizontal. The particle, of mass 4 kg , is released from rest at a point \(A\) and travels down the plane, passing through a point \(B\). The distance \(A B\) is 5 m . \includegraphics[max width=\textwidth, alt={}, center]{9d039ec3-fd0a-40ae-9afe-7627439081df-04_371_693_500_680}
  1. Find the potential energy lost as the particle moves from point \(A\) to point \(B\).
  2. Hence write down the kinetic energy of the particle when it reaches point \(B\).
  3. Hence find the speed of the particle when it reaches point \(B\).

Question 2:
Part (a)
AnswerMarks Guidance
AnswerMark Guidance
\(\Delta PE = mgh = 4 \times 9.8 \times 5\sin 20°\)M1 Correct use of \(mgs\sin\theta\)
\(= 67.0\) J (67.08…)A1 Accept \(g = 9.81\) giving \(67.4\) J
Part (b)
AnswerMarks Guidance
AnswerMark Guidance
\(KE = 67.0\) J (equal to PE lost, from (a))B1 Follow through from (a)
Part (c)
AnswerMarks Guidance
AnswerMark Guidance
\(\frac{1}{2}mv^2 = 67.0\)M1 Use of \(KE = \frac{1}{2}mv^2\) with their (b)
\(v = \sqrt{\frac{2 \times 67.0}{4}} = 5.79\) m s\(^{-1}\)A1 Correct final answer
# Question 2:

## Part (a)
| Answer | Mark | Guidance |
|--------|------|----------|
| $\Delta PE = mgh = 4 \times 9.8 \times 5\sin 20°$ | M1 | Correct use of $mgs\sin\theta$ |
| $= 67.0$ J (67.08…) | A1 | Accept $g = 9.81$ giving $67.4$ J |

## Part (b)
| Answer | Mark | Guidance |
|--------|------|----------|
| $KE = 67.0$ J (equal to PE lost, from (a)) | B1 | Follow through from (a) |

## Part (c)
| Answer | Mark | Guidance |
|--------|------|----------|
| $\frac{1}{2}mv^2 = 67.0$ | M1 | Use of $KE = \frac{1}{2}mv^2$ with their (b) |
| $v = \sqrt{\frac{2 \times 67.0}{4}} = 5.79$ m s$^{-1}$ | A1 | Correct final answer |

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2 A particle is placed on a smooth plane which is inclined at an angle of $20 ^ { \circ }$ to the horizontal. The particle, of mass 4 kg , is released from rest at a point $A$ and travels down the plane, passing through a point $B$. The distance $A B$ is 5 m .\\
\includegraphics[max width=\textwidth, alt={}, center]{9d039ec3-fd0a-40ae-9afe-7627439081df-04_371_693_500_680}
\begin{enumerate}[label=(\alph*)]
\item Find the potential energy lost as the particle moves from point $A$ to point $B$.
\item Hence write down the kinetic energy of the particle when it reaches point $B$.
\item Hence find the speed of the particle when it reaches point $B$.
\end{enumerate}

\hfill \mbox{\textit{AQA M2 2011 Q2 [5]}}