CAIE M2 2013 November — Question 2 6 marks

Exam BoardCAIE
ModuleM2 (Mechanics 2)
Year2013
SessionNovember
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicVariable acceleration (1D)
TypeVelocity from acceleration by integration
DifficultyModerate -0.5 This is a straightforward variable acceleration problem requiring integration of a given acceleration function (though the function appears corrupted in the question text), applying initial conditions, and integrating velocity to find displacement. These are standard M2 techniques with no novel problem-solving required, making it slightly easier than average but still requiring multiple calculus steps.
Spec1.08a Fundamental theorem of calculus: integration as reverse of differentiation3.02f Non-uniform acceleration: using differentiation and integration

A particle moves in a straight line. At time \(t\) seconds its velocity is \(v\) ms\(^{-1}\) and its acceleration is \(a\) ms\(^{-2}\).
  1. Given that \(a = —\), express \(v\) in terms of \(t\).
  2. Given that \(v = tv\) when \(t = 0\), find \(v\) in terms of \(t\).
  3. Find the displacement from the starting point when \(t = v\).
[6]

Question 2:

AnswerMarks Guidance
2 (i)0.5vdv/dx = 0.5g – 0.015x2
vdv/dx = 10 – 0.03x2 AGM1
A1[2] N2L 2 forces
(ii)18.3 m B1
10/0.03 =18.257..
AnswerMarks
(iii)∫ vdv = ∫ (10–0.03x2 )dx
v2 /2 = 10x – 0.03x3 /3 (+c)
v2 /2 = 10× 18.3 – 0.03×18.3 3 /3
AnswerMarks
v = 15.6 ms −1M1
A1
M1
AnswerMarks Guidance
A1[4] Attempts to integrate
Accept omission of c
v2
AnswerMarks
Uses ans (ii) in formula for7
Question 2:
--- 2 (i) ---
2 (i) | 0.5vdv/dx = 0.5g – 0.015x2
vdv/dx = 10 – 0.03x2 AG | M1
A1 | [2] | N2L 2 forces
(ii) | 18.3 m | B1 | [1] | ( )
10/0.03 =18.257..
(iii) | ∫ vdv = ∫ (10–0.03x2 )dx
v2 /2 = 10x – 0.03x3 /3 (+c)
v2 /2 = 10× 18.3 – 0.03×18.3 3 /3
v = 15.6 ms −1 | M1
A1
M1
A1 | [4] | Attempts to integrate
Accept omission of c
v2
Uses ans (ii) in formula for | 7
A particle moves in a straight line. At time $t$ seconds its velocity is $v$ ms$^{-1}$ and its acceleration is $a$ ms$^{-2}$.

\begin{enumerate}[label=(\roman*)]
\item Given that $a = —$, express $v$ in terms of $t$.
\item Given that $v = tv$ when $t = 0$, find $v$ in terms of $t$.
\item Find the displacement from the starting point when $t = v$.
\end{enumerate}
[6]

\hfill \mbox{\textit{CAIE M2 2013 Q2 [6]}}