CAIE M1 2005 November — Question 5 9 marks

Exam BoardCAIE
ModuleM1 (Mechanics 1)
Year2005
SessionNovember
Marks9
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicTravel graphs
TypeDisplacement-time graph interpretation or sketching
DifficultyStandard +0.3 This is a structured multi-part question requiring interpretation of a displacement-time graph and conversion to velocity-time, with straightforward SUVAT calculations. While it involves multiple steps and understanding of tangent gradients representing velocity, each part follows standard mechanics procedures without requiring novel insight or complex problem-solving beyond typical M1 level.
Spec3.02a Kinematics language: position, displacement, velocity, acceleration3.02b Kinematic graphs: displacement-time and velocity-time3.02c Interpret kinematic graphs: gradient and area

5 \includegraphics[max width=\textwidth, alt={}, center]{2026cad4-8494-4139-ad21-d8a17ac2b955-3_917_1451_1059_347} The diagram shows the displacement-time graph for a car's journey. The graph consists of two curved parts \(A B\) and \(C D\), and a straight line \(B C\). The line \(B C\) is a tangent to the curve \(A B\) at \(B\) and a tangent to the curve \(C D\) at \(C\). The gradient of the curves at \(t = 0\) and \(t = 600\) is zero, and the acceleration of the car is constant for \(0 < t < 80\) and for \(560 < t < 600\). The displacement of the car is 400 m when \(t = 80\).
  1. Sketch the velocity-time graph for the journey.
  2. Find the velocity at \(t = 80\).
  3. Find the total distance for the journey.
  4. Find the acceleration of the car for \(0 < t < 80\).

Question 5:
Part (i)
AnswerMarks Guidance
Answer/WorkingMark Guidance
\(v\)-\(t\) graph with 3 straight line segmentsM1 For 3 straight line segments; \(v(t)\) positive for \(0 < t < 600\), continuous and single valued
End points at \(t=0\), \(t=600\) on \(t\)-axisA1 End points (\(t=0\), \(t=600\)) on \(t\)-axis
\(t = 80\), \(t = 560\), \(t = 600\) marked; +ve, zero, \(-\)ve gradients in orderA1 \(+\)ve, zero and \(-\)ve gradients in order
Part (ii)
AnswerMarks Guidance
Answer/WorkingMark Guidance
\(\frac{1}{2} \times 80 \times v = 400\)M1 For using the idea that area of triangle represents distance, or using \(\frac{(0+v)}{2} = s \div t\)
Velocity is \(10\ \text{ms}^{-1}\)A1
Part (iii)
AnswerMarks Guidance
Answer/WorkingMark Guidance
\(D = \frac{1}{2}(600 + 480) \times 10\)M1 For using the idea that area of trapezium represents total distance
Total distance is \(5400\) mA1ft
Part (iv)
AnswerMarks Guidance
Answer/WorkingMark Guidance
Acceleration is \(0.125\ \text{ms}^{-2}\) for \(0 < t < 80\)M1, A1ft For using the idea that gradient represents acceleration, or for using \(v = 0 + at\)
## Question 5:

### Part (i)
| Answer/Working | Mark | Guidance |
|---|---|---|
| $v$-$t$ graph with 3 straight line segments | M1 | For 3 straight line segments; $v(t)$ positive for $0 < t < 600$, continuous and single valued |
| End points at $t=0$, $t=600$ on $t$-axis | A1 | End points ($t=0$, $t=600$) on $t$-axis |
| $t = 80$, $t = 560$, $t = 600$ marked; +ve, zero, $-$ve gradients in order | A1 | $+$ve, zero and $-$ve gradients in order |

### Part (ii)
| Answer/Working | Mark | Guidance |
|---|---|---|
| $\frac{1}{2} \times 80 \times v = 400$ | M1 | For using the idea that area of triangle represents distance, or using $\frac{(0+v)}{2} = s \div t$ |
| Velocity is $10\ \text{ms}^{-1}$ | A1 | |

### Part (iii)
| Answer/Working | Mark | Guidance |
|---|---|---|
| $D = \frac{1}{2}(600 + 480) \times 10$ | M1 | For using the idea that area of trapezium represents total distance |
| Total distance is $5400$ m | A1ft | |

### Part (iv)
| Answer/Working | Mark | Guidance |
|---|---|---|
| Acceleration is $0.125\ \text{ms}^{-2}$ for $0 < t < 80$ | M1, A1ft | For using the idea that gradient represents acceleration, or for using $v = 0 + at$ |

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5\\
\includegraphics[max width=\textwidth, alt={}, center]{2026cad4-8494-4139-ad21-d8a17ac2b955-3_917_1451_1059_347}

The diagram shows the displacement-time graph for a car's journey. The graph consists of two curved parts $A B$ and $C D$, and a straight line $B C$. The line $B C$ is a tangent to the curve $A B$ at $B$ and a tangent to the curve $C D$ at $C$. The gradient of the curves at $t = 0$ and $t = 600$ is zero, and the acceleration of the car is constant for $0 < t < 80$ and for $560 < t < 600$. The displacement of the car is 400 m when $t = 80$.\\
(i) Sketch the velocity-time graph for the journey.\\
(ii) Find the velocity at $t = 80$.\\
(iii) Find the total distance for the journey.\\
(iv) Find the acceleration of the car for $0 < t < 80$.

\hfill \mbox{\textit{CAIE M1 2005 Q5 [9]}}