Edexcel FM2 2024 June — Question 5 11 marks

Exam BoardEdexcel
ModuleFM2 (Further Mechanics 2)
Year2024
SessionJune
Marks11
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicSimple Harmonic Motion
TypeFind amplitude from speed conditions
DifficultyStandard +0.8 This is a multi-part SHM question requiring knowledge of the standard equations (v² = ω²(a² - x²) and max acceleration = ω²a), algebraic manipulation to find amplitude, and integration/inverse trig for part (c). While the techniques are standard for FM2, the question requires careful application across three parts with the final part being non-routine, placing it moderately above average difficulty.
Spec4.10f Simple harmonic motion: x'' = -omega^2 x

  1. A particle \(P\) moves in a straight line with simple harmonic motion about a fixed point \(O\). The magnitude of the greatest acceleration of \(P\) is \(18 \mathrm {~m} \mathrm {~s} ^ { - 2 }\)
When \(P\) is 0.3 m from \(O\), the speed of \(P\) is \(2.4 \mathrm {~ms} ^ { - 1 }\) The amplitude of the motion is \(a\) metres.
  1. Show that \(a = 0.5\)
  2. Find the greatest speed of \(P\). During one oscillation, the speed of \(P\) is at least \(2 \mathrm {~ms} ^ { - 1 }\) for \(S\) seconds.
  3. Find the value of \(S\).

5(a)
AnswerMarks Guidance
\(\omega^2 a = 18\)B1 3.4
Use \(v^2 = \omega^2(a^2 - x^2)\)M1 3.4
$2.4^2
## 5(a)

$\omega^2 a = 18$ | B1 | 3.4

Use $v^2 = \omega^2(a^2 - x^2)$ | M1 | 3.4

$2.4^2
\begin{enumerate}
  \item A particle $P$ moves in a straight line with simple harmonic motion about a fixed point $O$. The magnitude of the greatest acceleration of $P$ is $18 \mathrm {~m} \mathrm {~s} ^ { - 2 }$
\end{enumerate}

When $P$ is 0.3 m from $O$, the speed of $P$ is $2.4 \mathrm {~ms} ^ { - 1 }$\\
The amplitude of the motion is $a$ metres.\\
(a) Show that $a = 0.5$\\
(b) Find the greatest speed of $P$.

During one oscillation, the speed of $P$ is at least $2 \mathrm {~ms} ^ { - 1 }$ for $S$ seconds.\\
(c) Find the value of $S$.

\hfill \mbox{\textit{Edexcel FM2 2024 Q5 [11]}}