CAIE M2 2008 November — Question 1 4 marks

Exam BoardCAIE
ModuleM2 (Mechanics 2)
Year2008
SessionNovember
Marks4
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicVariable Force
TypeElastic string with variable force
DifficultyStandard +0.3 This is a straightforward application of Hooke's law and Newton's second law. Students must find the extension (6 - 2.5 = 3.5 m), calculate the tension using T = (λx)/l, then apply F = ma with weight and tension. It's a standard single-step mechanics problem requiring only direct formula application, making it slightly easier than average.
Spec6.02e Calculate KE and PE: using formulae6.02h Elastic PE: 1/2 k x^2

1 One end of a light elastic rope of natural length 2.5 m and modulus of elasticity 80 N is attached to a fixed point \(A\). A stone \(S\) of mass 8 kg is attached to the other end of the rope. \(S\) is held at a point 6 m vertically below \(A\) and then released. Find the initial acceleration of \(S\).

Question 1:
AnswerMarks Guidance
Answer/WorkingMark Guidance
\(T = 80 \times 3.5/2.5 (= 112)\)M1 For using \(T = \lambda x / L\)
M1For using Newton's second law
\(8a = T - 8g\)A1
Acceleration is \(4 \text{ ms}^{-2}\)A1 [4]
## Question 1:

| Answer/Working | Mark | Guidance |
|---|---|---|
| $T = 80 \times 3.5/2.5 (= 112)$ | M1 | For using $T = \lambda x / L$ |
| | M1 | For using Newton's second law |
| $8a = T - 8g$ | A1 | |
| Acceleration is $4 \text{ ms}^{-2}$ | A1 | **[4]** |

---
1 One end of a light elastic rope of natural length 2.5 m and modulus of elasticity 80 N is attached to a fixed point $A$. A stone $S$ of mass 8 kg is attached to the other end of the rope. $S$ is held at a point 6 m vertically below $A$ and then released. Find the initial acceleration of $S$.

\hfill \mbox{\textit{CAIE M2 2008 Q1 [4]}}