AQA M1 2013 January — Question 1 14 marks

Exam BoardAQA
ModuleM1 (Mechanics 1)
Year2013
SessionJanuary
Marks14
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicConstant acceleration (SUVAT)
TypeAverage speed or total distance calculation
DifficultyModerate -0.8 This is a straightforward multi-part SUVAT question where all necessary parameters are given explicitly for each stage. Students simply need to select and apply standard kinematic equations (s=½(u+v)t, v=u+at, s=ut+½at²) without any problem-solving insight or tricky setup. The calculations are routine and the question structure guides students through each step methodically.
Spec3.02d Constant acceleration: SUVAT formulae

1 A car travels on a straight horizontal race track. The car decelerates uniformly from a speed of \(20 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) to a speed of \(12 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) as it travels a distance of 640 metres. The car then accelerates uniformly, travelling a further 1820 metres in 70 seconds.
    1. Find the time that it takes the car to travel the first 640 metres.
    2. Find the deceleration of the car during the first 640 metres.
    1. Find the acceleration of the car as it travels the further 1820 metres.
    2. Find the speed of the car when it has completed the further 1820 metres.
  1. Find the average speed of the car as it travels the 2460 metres.

Question 1:
Part (a)(i)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\(s = \frac{1}{2}(u+v)t\)M1 Use of correct suvat equation
\(640 = \frac{1}{2}(20+12)t\)M1 Correct substitution
\(t = 40\) secondsA1 cao
Part (a)(ii)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\(v^2 = u^2 + 2as\) or \(v = u + at\)M1 Use of correct suvat
\(144 = 400 + 2a(640)\) or \(12 = 20 + 40a\)M1 Correct substitution
\(a = -0.25 \text{ ms}^{-2}\), deceleration \(= 0.25 \text{ ms}^{-2}\)A1 Accept \(\frac{1}{4}\)
Part (b)(i)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\(s = ut + \frac{1}{2}at^2\)M1 Use of correct suvat with \(u=12\), \(t=70\)
\(1820 = 12(70) + \frac{1}{2}a(70)^2\)M1 Correct substitution
\(a = \frac{2(1820-840)}{4900} = 0.4 \text{ ms}^{-2}\)A1 cao
Part (b)(ii)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\(v = u + at\)M1 ft their acceleration
\(v = 12 + 0.4 \times 70\)M1 Correct substitution
\(v = 40 \text{ ms}^{-1}\)A1 cao
Part (c)
AnswerMarks Guidance
Answer/WorkingMarks Guidance
Total time \(= 40 + 70 = 110\) secondsM1 Correct total time and distance
Average speed \(= \frac{2460}{110} = \frac{246}{11} \approx 22.4 \text{ ms}^{-1}\)A1 cao
# Question 1:

## Part (a)(i)
| Answer/Working | Marks | Guidance |
|---|---|---|
| $s = \frac{1}{2}(u+v)t$ | M1 | Use of correct suvat equation |
| $640 = \frac{1}{2}(20+12)t$ | M1 | Correct substitution |
| $t = 40$ seconds | A1 | cao |

## Part (a)(ii)
| Answer/Working | Marks | Guidance |
|---|---|---|
| $v^2 = u^2 + 2as$ or $v = u + at$ | M1 | Use of correct suvat |
| $144 = 400 + 2a(640)$ or $12 = 20 + 40a$ | M1 | Correct substitution |
| $a = -0.25 \text{ ms}^{-2}$, deceleration $= 0.25 \text{ ms}^{-2}$ | A1 | Accept $\frac{1}{4}$ |

## Part (b)(i)
| Answer/Working | Marks | Guidance |
|---|---|---|
| $s = ut + \frac{1}{2}at^2$ | M1 | Use of correct suvat with $u=12$, $t=70$ |
| $1820 = 12(70) + \frac{1}{2}a(70)^2$ | M1 | Correct substitution |
| $a = \frac{2(1820-840)}{4900} = 0.4 \text{ ms}^{-2}$ | A1 | cao |

## Part (b)(ii)
| Answer/Working | Marks | Guidance |
|---|---|---|
| $v = u + at$ | M1 | ft their acceleration |
| $v = 12 + 0.4 \times 70$ | M1 | Correct substitution |
| $v = 40 \text{ ms}^{-1}$ | A1 | cao |

## Part (c)
| Answer/Working | Marks | Guidance |
|---|---|---|
| Total time $= 40 + 70 = 110$ seconds | M1 | Correct total time and distance |
| Average speed $= \frac{2460}{110} = \frac{246}{11} \approx 22.4 \text{ ms}^{-1}$ | A1 | cao |

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1 A car travels on a straight horizontal race track. The car decelerates uniformly from a speed of $20 \mathrm {~m} \mathrm {~s} ^ { - 1 }$ to a speed of $12 \mathrm {~m} \mathrm {~s} ^ { - 1 }$ as it travels a distance of 640 metres. The car then accelerates uniformly, travelling a further 1820 metres in 70 seconds.
\begin{enumerate}[label=(\alph*)]
\item \begin{enumerate}[label=(\roman*)]
\item Find the time that it takes the car to travel the first 640 metres.
\item Find the deceleration of the car during the first 640 metres.
\end{enumerate}\item \begin{enumerate}[label=(\roman*)]
\item Find the acceleration of the car as it travels the further 1820 metres.
\item Find the speed of the car when it has completed the further 1820 metres.
\end{enumerate}\item Find the average speed of the car as it travels the 2460 metres.
\end{enumerate}

\hfill \mbox{\textit{AQA M1 2013 Q1 [14]}}