AQA M1 2014 June — Question 2 5 marks

Exam BoardAQA
ModuleM1 (Mechanics 1)
Year2014
SessionJune
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicForces, equilibrium and resultants
TypeEquilibrium of particle under coplanar forces
DifficultyModerate -0.8 This is a straightforward two-dimensional equilibrium problem requiring resolution of forces in perpendicular directions and basic trigonometry. Students need only apply F cos θ = 60 and F sin θ = 40, then use Pythagoras and inverse tan—standard M1 bookwork with no problem-solving insight required.
Spec3.03m Equilibrium: sum of resolved forces = 03.03n Equilibrium in 2D: particle under forces

2 Three forces are in equilibrium in a vertical plane, as shown in the diagram. There is a vertical force of magnitude 40 N and a horizontal force of magnitude 60 N . The third force has magnitude \(F\) newtons and acts at an angle \(\theta\) above the horizontal. \includegraphics[max width=\textwidth, alt={}, center]{788534a5-abbb-4d6a-87b2-c54e859a128a-04_490_894_456_571}
  1. \(\quad\) Find \(F\).
  2. \(\quad\) Find \(\theta\).

Question 2:
Part (a)
AnswerMarks Guidance
\(F\cos\theta = 60\) and \(F\sin\theta = 40\)M1 Resolving horizontally and vertically
\(F = \sqrt{60^2 + 40^2}\)
\(F = \sqrt{5200} = 72.1 \text{ N}\)A1 Accept \(20\sqrt{13}\)
Part (b)
AnswerMarks Guidance
\(\tan\theta = \frac{40}{60}\)M1 Correct trig ratio
A1Correct equation
\(\theta = 33.7°\)A1 cao
# Question 2:

## Part (a)
| $F\cos\theta = 60$ and $F\sin\theta = 40$ | M1 | Resolving horizontally and vertically |
|---|---|---|
| $F = \sqrt{60^2 + 40^2}$ | | |
| $F = \sqrt{5200} = 72.1 \text{ N}$ | A1 | Accept $20\sqrt{13}$ |

## Part (b)
| $\tan\theta = \frac{40}{60}$ | M1 | Correct trig ratio |
|---|---|---|
| | A1 | Correct equation |
| $\theta = 33.7°$ | A1 | cao |

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2 Three forces are in equilibrium in a vertical plane, as shown in the diagram. There is a vertical force of magnitude 40 N and a horizontal force of magnitude 60 N . The third force has magnitude $F$ newtons and acts at an angle $\theta$ above the horizontal.\\
\includegraphics[max width=\textwidth, alt={}, center]{788534a5-abbb-4d6a-87b2-c54e859a128a-04_490_894_456_571}
\begin{enumerate}[label=(\alph*)]
\item $\quad$ Find $F$.
\item $\quad$ Find $\theta$.
\end{enumerate}

\hfill \mbox{\textit{AQA M1 2014 Q2 [5]}}