CAIE Further Paper 3 2024 November — Question 2 5 marks

Exam BoardCAIE
ModuleFurther Paper 3 (Further Paper 3)
Year2024
SessionNovember
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicCircular Motion 1
DifficultyChallenging +1.2 This is a standard circular motion problem requiring energy conservation and Newton's second law for circular motion. While it involves multiple steps (finding speed at B using energy, then applying F=ma radially), the approach is methodical and well-practiced. The geometry with tan θ = 3/4 is straightforward (giving sin θ = 3/5, cos θ = 4/5). It's slightly above average difficulty due to the coordinate geometry and careful bookkeeping of height changes, but remains a textbook application of core principles without requiring novel insight.
Spec3.03c Newton's second law: F=ma one dimension6.02i Conservation of energy: mechanical energy principle6.05d Variable speed circles: energy methods

A particle \(P\) of mass \(m\) is attached to one end of a light inextensible string of length \(a\). The other end of the string is attached to a fixed point \(O\). The particle \(P\) is held at the point \(A\) with the string taut. It is given that \(OA\) makes an angle \(\theta\) with the downward vertical through \(O\), where \(\tan \theta = \frac{3}{4}\). The particle \(P\) is projected perpendicular to \(OA\) in an upwards direction with speed \(\sqrt{5ag}\), and it starts to move along a circular path in a vertical plane. When \(P\) is at the point \(B\), where angle \(AOB\) is a right angle, the tension in the string is \(T\). Find \(T\) in terms of \(m\) and \(g\). [5]

Question 2:
AnswerMarks
2mv2
At B, T+mgsin=
AnswerMarks
aB1
1 1
Energy A to B: mu2 − mv2 =mga(cos+sin)
AnswerMarks
2 2M1A1
Substitute for u and  to find T:
 4 3
T =mg5−2 −3 
AnswerMarks
 5 5M1
8
T = mg
AnswerMarks
5A1
5
AnswerMarks Guidance
QuestionAnswer Marks
Question 2:
2 | mv2
At B, T+mgsin=
a | B1
1 1
Energy A to B: mu2 − mv2 =mga(cos+sin)
2 2 | M1A1
Substitute for u and  to find T:
 4 3
T =mg5−2 −3 
 5 5 | M1
8
T = mg
5 | A1
5
Question | Answer | Marks | Guidance
A particle $P$ of mass $m$ is attached to one end of a light inextensible string of length $a$. The other end of the string is attached to a fixed point $O$. The particle $P$ is held at the point $A$ with the string taut. It is given that $OA$ makes an angle $\theta$ with the downward vertical through $O$, where $\tan \theta = \frac{3}{4}$. The particle $P$ is projected perpendicular to $OA$ in an upwards direction with speed $\sqrt{5ag}$, and it starts to move along a circular path in a vertical plane. When $P$ is at the point $B$, where angle $AOB$ is a right angle, the tension in the string is $T$.

Find $T$ in terms of $m$ and $g$. [5]

\hfill \mbox{\textit{CAIE Further Paper 3 2024 Q2 [5]}}