AQA M2 2010 January — Question 6 7 marks

Exam BoardAQA
ModuleM2 (Mechanics 2)
Year2010
SessionJanuary
Marks7
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicCircular Motion 1
TypeConical pendulum – horizontal circle in free space (no surface)
DifficultyModerate -0.3 This is a standard conical pendulum problem requiring basic trigonometry (radius = L sin θ) and resolving forces with circular motion (T cos θ = mg, T sin θ = mrω²). The setup is straightforward with clear given values, making it slightly easier than average but still requiring proper application of mechanics principles.
Spec6.05b Circular motion: v=r*omega and a=v^2/r6.05c Horizontal circles: conical pendulum, banked tracks

6 A particle, of mass 4 kg , is attached to one end of a light inextensible string of length 1.2 metres. The other end of the string is attached to a fixed point \(O\). The particle moves in a horizontal circle at a constant speed. The angle between the string and the vertical is \(\theta\). \includegraphics[max width=\textwidth, alt={}, center]{06b431ca-d3a8-46d6-b9f8-bac08d3fd51e-4_529_554_1580_737}
  1. Find the radius of the horizontal circle in terms of \(\theta\).
  2. The angular speed of the particle is 5 radians per second. Find \(\theta\).

Question 6:
Part (a):
AnswerMarks Guidance
\(r = 1.2\sin\theta\)B1 \(1.2\cos\theta\) scores 0 marks
Part (b):
AnswerMarks Guidance
Resolve horizontally: \(T\sin\theta = m\omega^2 r\)M1A1 \(T\cos\theta = m\omega^2 r\) etc scores M1 (+ second M1)
\(T\sin\theta = 4 \times 5^2 \times 1.2\sin\theta\), so \(T = 120\)A1
Resolve vertically: \(T\cos\theta = 4g\)M1A1 M1 for \(\tan\theta = \frac{30\sin\theta}{g}\)
\(\cos\theta = 0.32666\)
\(\theta = 70.9°\) or \(1.24^c\)A1 Total: 6
## Question 6:

**Part (a):**
| $r = 1.2\sin\theta$ | B1 | $1.2\cos\theta$ scores 0 marks |

**Part (b):**
| Resolve horizontally: $T\sin\theta = m\omega^2 r$ | M1A1 | $T\cos\theta = m\omega^2 r$ etc scores M1 (+ second M1) |
| $T\sin\theta = 4 \times 5^2 \times 1.2\sin\theta$, so $T = 120$ | A1 | |
| Resolve vertically: $T\cos\theta = 4g$ | M1A1 | M1 for $\tan\theta = \frac{30\sin\theta}{g}$ |
| $\cos\theta = 0.32666$ | | |
| $\theta = 70.9°$ or $1.24^c$ | A1 | Total: 6 |

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6 A particle, of mass 4 kg , is attached to one end of a light inextensible string of length 1.2 metres. The other end of the string is attached to a fixed point $O$. The particle moves in a horizontal circle at a constant speed. The angle between the string and the vertical is $\theta$.\\
\includegraphics[max width=\textwidth, alt={}, center]{06b431ca-d3a8-46d6-b9f8-bac08d3fd51e-4_529_554_1580_737}
\begin{enumerate}[label=(\alph*)]
\item Find the radius of the horizontal circle in terms of $\theta$.
\item The angular speed of the particle is 5 radians per second. Find $\theta$.
\end{enumerate}

\hfill \mbox{\textit{AQA M2 2010 Q6 [7]}}