Edexcel M1 2011 June — Question 1 8 marks

Exam BoardEdexcel
ModuleM1 (Mechanics 1)
Year2011
SessionJune
Marks8
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicVariable acceleration (1D)
TypeFinding when particle at rest
DifficultyModerate -0.8 This is a straightforward application of SUVAT equations for vertical motion under gravity. Part (a) uses v²=u²+2as with standard values, and part (b) requires solving a quadratic equation using s=ut+½at². Both parts are routine textbook exercises with no problem-solving insight required, making this easier than average but not trivial due to the algebraic manipulation needed.
Spec3.02d Constant acceleration: SUVAT formulae3.02h Motion under gravity: vector form

At time \(t = 0\) a ball is projected vertically upwards from a point \(O\) and rises to a maximum height of 40 m above \(O\). The ball is modelled as a particle moving freely under gravity.
  1. Show that the speed of projection is 28 m s\(^{-1}\). [3]
  2. Find the times, in seconds, when the ball is 33.6 m above \(O\). [5]

(a)
AnswerMarks Guidance
\(0^2 = u^2 - 2 \times 9.8 \times 40\)M1 A1
\(u = 28 \text{ m s}^{-1}\)A1 GIVEN ANSWER
(3)
(b)
AnswerMarks
\(33.6 = 28t - \frac{1}{2} \times 9.8t^2\)M1 A1
\(4.9t^2 - 28t + 33.6 = 0\)
\(t = \frac{28 \pm \sqrt{28^2 - 4 \times 4.9 \times 33.6}}{9.8}\)M1
\(= 4 \text{ s or } (1.7 \text{ s or } 1.71 \text{ s})\)A1 A1
(5)
8
## (a)
$0^2 = u^2 - 2 \times 9.8 \times 40$ | M1 A1 | 
$u = 28 \text{ m s}^{-1}$ | A1 | **GIVEN ANSWER**
| (3) |

## (b)
$33.6 = 28t - \frac{1}{2} \times 9.8t^2$ | M1 A1 |
$4.9t^2 - 28t + 33.6 = 0$ | |
$t = \frac{28 \pm \sqrt{28^2 - 4 \times 4.9 \times 33.6}}{9.8}$ | M1 |
$= 4 \text{ s or } (1.7 \text{ s or } 1.71 \text{ s})$ | A1 A1 |
| (5) |
| **8** |

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At time $t = 0$ a ball is projected vertically upwards from a point $O$ and rises to a maximum height of 40 m above $O$. The ball is modelled as a particle moving freely under gravity.

\begin{enumerate}[label=(\alph*)]
\item Show that the speed of projection is 28 m s$^{-1}$. [3]

\item Find the times, in seconds, when the ball is 33.6 m above $O$. [5]
\end{enumerate}

\hfill \mbox{\textit{Edexcel M1 2011 Q1 [8]}}