Edexcel FM1 Specimen — Question 2 6 marks

Exam BoardEdexcel
ModuleFM1 (Further Mechanics 1)
SessionSpecimen
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicMotion on a slope
TypeMotion up rough slope
DifficultyStandard +0.3 This is a straightforward Further Mechanics question requiring application of the work-energy principle to motion on a rough slope. While it's FM1 content (making it slightly harder than standard A-level), it's a standard textbook exercise with clear given values and a direct method. The work-energy approach simplifies what would otherwise be a SUVAT problem, and all necessary information is provided. Part (b) is a standard modelling critique requiring minimal insight.
Spec3.03v Motion on rough surface: including inclined planes6.02c Work by variable force: using integration6.02i Conservation of energy: mechanical energy principle

  1. A parcel of mass 5 kg is projected with speed \(8 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) up a line of greatest slope of a fixed rough inclined ramp.
    The ramp is inclined at angle \(\alpha\) to the horizontal, where \(\sin \alpha = \frac { 1 } { 7 }\) The parcel is projected from the point \(A\) on the ramp and comes to instantaneous rest at the point \(B\) on the ramp, where \(A B = 14 \mathrm {~m}\).
The coefficient of friction between the parcel and the ramp is \(\mu\).
In a model of the parcel's motion, the parcel is treated as a particle.
  1. Use the work-energy principle to find the value of \(\mu\).
  2. Suggest one way in which the model could be refined to make it more realistic.

Question 2:
Part (a):
AnswerMarks Guidance
Answer/WorkingMark Guidance
\(R = 5g\cos\alpha \left(= 5g \times \frac{4\sqrt{3}}{7} = 48.497...\right)\)M1 Condone sin/cos confusion
Force due to friction \(= \mu \times 5g\cos\alpha\)M1 Use of \(\mu\times\) their R
Work-Energy equationM1 Must use work-energy; requires all terms; condone sin/cos confusion, sign errors and their \(R\)
\(\frac{1}{2}\times 5\times 64 = 5\times 9.8\times 14\sin\alpha + 14\mu R\)A1 Correct in \(\theta\) and \(\mu R\)
\(\mu = 0.0913\) or \(0.091\)A1 Accept 0.0913 or 0.091
Part (b):
AnswerMarks Guidance
Answer/WorkingMark Guidance
Appropriate refinement, e.g. do not model the parcel as a particle and therefore take air resistance into account; take into account the dimensions/uniformity of the parcelB1
## Question 2:

**Part (a):**

| Answer/Working | Mark | Guidance |
|---|---|---|
| $R = 5g\cos\alpha \left(= 5g \times \frac{4\sqrt{3}}{7} = 48.497...\right)$ | M1 | Condone sin/cos confusion |
| Force due to friction $= \mu \times 5g\cos\alpha$ | M1 | Use of $\mu\times$ their R |
| Work-Energy equation | M1 | Must use work-energy; requires all terms; condone sin/cos confusion, sign errors and their $R$ |
| $\frac{1}{2}\times 5\times 64 = 5\times 9.8\times 14\sin\alpha + 14\mu R$ | A1 | Correct in $\theta$ and $\mu R$ |
| $\mu = 0.0913$ or $0.091$ | A1 | Accept 0.0913 **or** 0.091 |

**Part (b):**

| Answer/Working | Mark | Guidance |
|---|---|---|
| Appropriate refinement, e.g. do not model the parcel as a particle and therefore take air resistance into account; take into account the dimensions/uniformity of the parcel | B1 | |

---
\begin{enumerate}
  \item A parcel of mass 5 kg is projected with speed $8 \mathrm {~m} \mathrm {~s} ^ { - 1 }$ up a line of greatest slope of a fixed rough inclined ramp.\\
The ramp is inclined at angle $\alpha$ to the horizontal, where $\sin \alpha = \frac { 1 } { 7 }$\\
The parcel is projected from the point $A$ on the ramp and comes to instantaneous rest at the point $B$ on the ramp, where $A B = 14 \mathrm {~m}$.
\end{enumerate}

The coefficient of friction between the parcel and the ramp is $\mu$.\\
In a model of the parcel's motion, the parcel is treated as a particle.\\
(a) Use the work-energy principle to find the value of $\mu$.\\
(b) Suggest one way in which the model could be refined to make it more realistic.

\hfill \mbox{\textit{Edexcel FM1  Q2 [6]}}