Edexcel M1 2017 October — Question 6 14 marks

Exam BoardEdexcel
ModuleM1 (Mechanics 1)
Year2017
SessionOctober
Marks14
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicConstant acceleration (SUVAT)
DifficultyModerate -0.3 This is a standard SUVAT problem with multiple phases of motion requiring systematic application of kinematic equations. While it involves several steps and algebraic manipulation, the approach is methodical and follows a well-practiced template for multi-stage motion problems. The 'show that' structure provides scaffolding that guides students through the solution, making it slightly easier than average.
Spec3.02b Kinematic graphs: displacement-time and velocity-time3.02d Constant acceleration: SUVAT formulae

An athlete goes for a run along a straight horizontal road. Starting from rest, she accelerates at 0.6 m s\(^{-2}\) up to a speed of \(V\) m s\(^{-1}\). She then maintains this constant speed of \(V\) m s\(^{-1}\) before finally decelerating at 0.2 m s\(^{-2}\) back to rest. She covers a total distance of 1500 m in 270 s.
  1. Sketch a speed-time graph to represent the athlete's run. [2]
  2. Show that she accelerates for \(\frac{5V}{3}\) seconds. [2]
  3. Show that \(V^2 - kV + 450 = 0\), where \(k\) is a constant to be found. [6]
  4. Find the value of \(V\), justifying your answer. [4]

An athlete goes for a run along a straight horizontal road. Starting from rest, she accelerates at 0.6 m s$^{-2}$ up to a speed of $V$ m s$^{-1}$. She then maintains this constant speed of $V$ m s$^{-1}$ before finally decelerating at 0.2 m s$^{-2}$ back to rest. She covers a total distance of 1500 m in 270 s.

\begin{enumerate}[label=(\alph*)]
\item Sketch a speed-time graph to represent the athlete's run.
[2]
\item Show that she accelerates for $\frac{5V}{3}$ seconds.
[2]
\item Show that $V^2 - kV + 450 = 0$, where $k$ is a constant to be found.
[6]
\item Find the value of $V$, justifying your answer.
[4]
\end{enumerate}

\hfill \mbox{\textit{Edexcel M1 2017 Q6 [14]}}