OCR MEI M1 — Question 2 8 marks

Exam BoardOCR MEI
ModuleM1 (Mechanics 1)
Marks8
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicTravel graphs
TypeDistance from velocity function using calculus
DifficultyModerate -0.8 This is a straightforward M1 kinematics question requiring basic calculus operations: differentiate to find acceleration, solve a quadratic for zero velocity, and integrate to find distance. All techniques are standard with no conceptual challenges or novel problem-solving required, making it easier than average but not trivial due to the integration step.
Spec3.02a Kinematics language: position, displacement, velocity, acceleration3.02b Kinematic graphs: displacement-time and velocity-time3.02c Interpret kinematic graphs: gradient and area

A particle moves along the \(x\)-axis with velocity, \(v\) ms\(^{-1}\), at time \(t\) given by $$v = 24t - 6t^2.$$ The positive direction is in the sense of \(x\) increasing.
  1. Find an expression for the acceleration of the particle at time \(t\). [2]
  2. Find the times, \(t_1\) and \(t_2\), at which the particle has zero speed. [2]
  3. Find the distance travelled between the times \(t_1\) and \(t_2\). [4]

Question 2:

AnswerMarks Guidance
2(i)a=24−12t M1
A1Differentiate
cao2
(ii)Need 24t−6t2 =0
t = 0, 4M1
A1Equate v = 0 and attempt to factorise
(or solve). Award for one root found.
AnswerMarks
Both. cao.2
(iii)4
( 24t−6t2)
s=∫ dt
0
= ⎡12t2 −2t3⎤4
⎣ ⎦
0
(12×16−2×64)−0
AnswerMarks
= 64 mM1
A1
M1
AnswerMarks
A1Attempt to integrate. No limits required.
Either term correct. No limits required
Sub t = 4 in integral. Accept no bottom limit
substituted or arb const assumed 0. Accept reversed
limits. FT their limits.
cao. Award if seen.
[If trapezium rule used.
M1 At least 4 strips: M1 enough strips for 3 s. f.
AnswerMarks
A1 (dep on 2nd M1) One strip area correct: A1 cao]4
total8
Question 2:
--- 2(i) ---
2(i) | a=24−12t | M1
A1 | Differentiate
cao | 2
(ii) | Need 24t−6t2 =0
t = 0, 4 | M1
A1 | Equate v = 0 and attempt to factorise
(or solve). Award for one root found.
Both. cao. | 2
(iii) | 4
( 24t−6t2)
s=∫ dt
0
= ⎡12t2 −2t3⎤4
⎣ ⎦
0
(12×16−2×64)−0
= 64 m | M1
A1
M1
A1 | Attempt to integrate. No limits required.
Either term correct. No limits required
Sub t = 4 in integral. Accept no bottom limit
substituted or arb const assumed 0. Accept reversed
limits. FT their limits.
cao. Award if seen.
[If trapezium rule used.
M1 At least 4 strips: M1 enough strips for 3 s. f.
A1 (dep on 2nd M1) One strip area correct: A1 cao] | 4
total | 8
A particle moves along the $x$-axis with velocity, $v$ ms$^{-1}$, at time $t$ given by
$$v = 24t - 6t^2.$$
The positive direction is in the sense of $x$ increasing.

\begin{enumerate}[label=(\roman*)]
\item Find an expression for the acceleration of the particle at time $t$. [2]
\item Find the times, $t_1$ and $t_2$, at which the particle has zero speed. [2]
\item Find the distance travelled between the times $t_1$ and $t_2$. [4]
\end{enumerate}

\hfill \mbox{\textit{OCR MEI M1  Q2 [8]}}