CAIE M1 2017 November — Question 4 7 marks

Exam BoardCAIE
ModuleM1 (Mechanics 1)
Year2017
SessionNovember
Marks7
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicTravel graphs
TypeMulti-stage motion with velocity-time graph given
DifficultyModerate -0.3 This is a standard SUVAT/kinematics question requiring reading a velocity-time graph, calculating accelerations from gradients, using area under the graph for distance, and solving linear equations. All techniques are routine for M1 level with no novel problem-solving required, making it slightly easier than average.
Spec3.02b Kinematic graphs: displacement-time and velocity-time3.02c Interpret kinematic graphs: gradient and area

4 \includegraphics[max width=\textwidth, alt={}, center]{db1b5f31-1a41-44dd-ae9a-0c67336997eb-05_600_1155_262_497} The diagram shows the velocity-time graph of a particle which moves in a straight line. The graph consists of 5 straight line segments. The particle starts from rest at a point \(A\) at time \(t = 0\), and initially travels towards point \(B\) on the line.
  1. Show that the acceleration of the particle between \(t = 3.5\) and \(t = 6\) is \(- 10 \mathrm {~m} \mathrm {~s} ^ { - 2 }\).
  2. The acceleration of the particle between \(t = 6\) and \(t = 10\) is \(7.5 \mathrm {~ms} ^ { - 2 }\). When \(t = 10\) the velocity of the particle is \(V \mathrm {~m} \mathrm {~s} ^ { - 1 }\). Find the value of \(V\).
  3. The particle comes to rest at \(B\) at time \(T\) s. Given that the total distance travelled by the particle between \(t = 0\) and \(t = T\) is 100 m , find the value of \(T\).

Question 4(i):
AnswerMarks Guidance
AnswerMarks Guidance
Acceleration \(= \dfrac{(-25)}{2.5} = -10\) m s\(^{-2}\)B1 AG
Question 4(ii):
AnswerMarks Guidance
AnswerMarks Guidance
\(V = -15 + 7.5 \times 4\)M1 Using \(v\)–\(t\) graph OE
\(V = 15\) m s\(^{-1}\)A1
Question 4(iii):
AnswerMarks Guidance
AnswerMarks Guidance
Using \(v = 0\) at \(t = 4.5\) and \(t = 8\)B1
M1Attempting to use area to find total distance travelled
\(\frac{1}{2} \times (4.5 + 2) \times 10 + \frac{1}{2} \times (8 - 4.5) \times 15 + \frac{1}{2} \times (T - 8) \times 15 = 100\)M1 For setting up an equation for total distance travelled and solving for \(T\)
\(T = 13.5\)A1
## Question 4(i):

| Answer | Marks | Guidance |
|--------|-------|----------|
| Acceleration $= \dfrac{(-25)}{2.5} = -10$ m s$^{-2}$ | B1 | AG |

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## Question 4(ii):

| Answer | Marks | Guidance |
|--------|-------|----------|
| $V = -15 + 7.5 \times 4$ | M1 | Using $v$–$t$ graph OE |
| $V = 15$ m s$^{-1}$ | A1 | |

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## Question 4(iii):

| Answer | Marks | Guidance |
|--------|-------|----------|
| Using $v = 0$ at $t = 4.5$ and $t = 8$ | B1 | |
| | M1 | Attempting to use area to find total distance travelled |
| $\frac{1}{2} \times (4.5 + 2) \times 10 + \frac{1}{2} \times (8 - 4.5) \times 15 + \frac{1}{2} \times (T - 8) \times 15 = 100$ | M1 | For setting up an equation for total distance travelled and solving for $T$ |
| $T = 13.5$ | A1 | |

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4\\
\includegraphics[max width=\textwidth, alt={}, center]{db1b5f31-1a41-44dd-ae9a-0c67336997eb-05_600_1155_262_497}

The diagram shows the velocity-time graph of a particle which moves in a straight line. The graph consists of 5 straight line segments. The particle starts from rest at a point $A$ at time $t = 0$, and initially travels towards point $B$ on the line.\\
(i) Show that the acceleration of the particle between $t = 3.5$ and $t = 6$ is $- 10 \mathrm {~m} \mathrm {~s} ^ { - 2 }$.\\

(ii) The acceleration of the particle between $t = 6$ and $t = 10$ is $7.5 \mathrm {~ms} ^ { - 2 }$. When $t = 10$ the velocity of the particle is $V \mathrm {~m} \mathrm {~s} ^ { - 1 }$. Find the value of $V$.\\

(iii) The particle comes to rest at $B$ at time $T$ s. Given that the total distance travelled by the particle between $t = 0$ and $t = T$ is 100 m , find the value of $T$.\\

\hfill \mbox{\textit{CAIE M1 2017 Q4 [7]}}