Edexcel M2 2022 October — Question 2 5 marks

Exam BoardEdexcel
ModuleM2 (Mechanics 2)
Year2022
SessionOctober
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicAdvanced work-energy problems
TypeEngine power on road constant/variable speed
DifficultyStandard +0.3 This is a standard M2 power-resistance-incline problem requiring P=Fv to find driving force, then F=ma with component of weight down the slope minus resistance. It's slightly easier than average because the setup is straightforward with given values, requiring only routine application of well-practiced techniques with no conceptual surprises.
Spec3.03d Newton's second law: 2D vectors6.02l Power and velocity: P = Fv

2. A car of mass 900 kg is moving down a straight road which is inclined at an angle \(\alpha\) to the horizontal, where \(\sin \alpha = \frac { 1 } { 12 }\) The engine of the car is working at a constant rate of 15 kW .
The resistance to the motion of the car is modelled as a constant force of magnitude 400 N . Find the acceleration of the car at the instant when it is moving at \(16 \mathrm {~ms} ^ { - 1 }\)
VIAV SIHI NI IIIIIM ION OCVIIIV SIHI NI III IM I O N OCVIIV SIHI NI IIIIM I I ON OC
\section*{Qu}

Question 2:
AnswerMarks Guidance
Answer/WorkingMark Guidance
Use of \(P = Fv\)M1 Seen or implied e.g. \(F = \dfrac{15000}{16}\ (=937.5)\). Condone 15 in place of 15000 or extra zeros on 15000
Equation of motionM1 Need all terms. Condone sign errors and sin/cos confusion. Dimensionally consistent
\(F + 900g\sin\theta - 400 = 900a\)A1 Unsimplified equation in \(P\) or their \(F\) with at most one error
\(\dfrac{15000}{16} + 900g \times \dfrac{1}{12} - 400 = 900a\)A1 Correct unsimplified equation with \(F\) and \(\sin\theta\) substituted
\(a = 1.41\ (1.4)\ (\text{ms}^{-2})\)A1 3sf or 2sf
Total: (5)
# Question 2:

| Answer/Working | Mark | Guidance |
|---|---|---|
| Use of $P = Fv$ | M1 | Seen or implied e.g. $F = \dfrac{15000}{16}\ (=937.5)$. Condone 15 in place of 15000 or extra zeros on 15000 |
| Equation of motion | M1 | Need all terms. Condone sign errors and sin/cos confusion. Dimensionally consistent |
| $F + 900g\sin\theta - 400 = 900a$ | A1 | Unsimplified equation in $P$ or their $F$ with at most one error |
| $\dfrac{15000}{16} + 900g \times \dfrac{1}{12} - 400 = 900a$ | A1 | Correct unsimplified equation with $F$ and $\sin\theta$ substituted |
| $a = 1.41\ (1.4)\ (\text{ms}^{-2})$ | A1 | 3sf or 2sf |
| **Total: (5)** | | |

---
2. A car of mass 900 kg is moving down a straight road which is inclined at an angle $\alpha$ to the horizontal, where $\sin \alpha = \frac { 1 } { 12 }$

The engine of the car is working at a constant rate of 15 kW .\\
The resistance to the motion of the car is modelled as a constant force of magnitude 400 N .

Find the acceleration of the car at the instant when it is moving at $16 \mathrm {~ms} ^ { - 1 }$\\

\begin{center}
\begin{tabular}{|l|l|l|}
\hline
VIAV SIHI NI IIIIIM ION OC & VIIIV SIHI NI III IM I O N OC & VIIV SIHI NI IIIIM I I ON OC \\
\hline
\end{tabular}
\end{center}

\section*{Qu}

\hfill \mbox{\textit{Edexcel M2 2022 Q2 [5]}}