| Exam Board | CAIE |
|---|---|
| Module | M1 (Mechanics 1) |
| Year | 2023 |
| Session | November |
| Marks | 7 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Friction |
| Type | Horizontal force only - find mass or coefficient |
| Difficulty | Moderate -0.8 This is a straightforward two-part mechanics question testing standard friction concepts. Part (a) requires simple application of F=μR with R=mg (limiting equilibrium), while part (b) involves finding acceleration using F-μR=ma, then using a SUVAT equation (s=ut+½at²) for a specific time interval. Both parts are routine textbook exercises requiring only direct application of standard formulas with no problem-solving insight or multi-step reasoning. |
| Spec | 3.02d Constant acceleration: SUVAT formulae3.03u Static equilibrium: on rough surfaces3.03v Motion on rough surface: including inclined planes |
| Answer | Marks | Guidance |
|---|---|---|
| 4(a) | R = 0.2g | B1 |
| 1.2=0.2g | M1 | Resolve horizontally and using |
| Answer | Marks | Guidance |
|---|---|---|
| µ = 0.6 | A1 | oe |
| Answer | Marks | Guidance |
|---|---|---|
| 4(b) | 1.2−0.30.2g=0.2a | *M1 |
| Answer | Marks | Guidance |
|---|---|---|
| a = 3 | A1 | 0.6=0.2a only seen, allow with |
| Answer | Marks | Guidance |
|---|---|---|
| 2 2 | DM1 | 1 |
| Answer | Marks | Guidance |
|---|---|---|
| Distance = 13.5−6=7.5 m | A1 | www |
| Answer | Marks | Guidance |
|---|---|---|
| Question | Answer | Marks |
Question 4:
--- 4(a) ---
4(a) | R = 0.2g | B1
1.2=0.2g | M1 | Resolve horizontally and using
F = µR to get an equation in µ; 2
relevant terms.
µ = 0.6 | A1 | oe
3
--- 4(b) ---
4(b) | 1.2−0.30.2g=0.2a | *M1 | Resolve horizontally using
Newton’s Second Law; 3 relevant
terms; allow sign errors; R=0.2g
only.
a = 3 | A1 | 0.6=0.2a only seen, allow with
BOD, but if 0.6 as friction being
used as resultant force, this is
M0A0.
1 1
s =0+ 332 =13.5 s =0+ 322 =6
3 2
2 2 | DM1 | 1
For use of s=ut+ at2 (or a
2
complete method) to find a distance
at least once with u=0 and their
positive a and t=2 or t=3.
Distance = 13.5−6=7.5 m | A1 | www
4
Question | Answer | Marks | GuidanceA particle $P$ of mass 0.2 kg lies at rest on a rough horizontal plane. A horizontal force of 1.2 N is applied to $P$.
\begin{enumerate}[label=(\alph*)]
\item Given that $P$ is in limiting equilibrium, find the coefficient of friction between $P$ and the plane. [3]
\item Given instead that the coefficient of friction between $P$ and the plane is 0.3, find the distance travelled by $P$ in the third second of its motion. [4]
\end{enumerate}
\hfill \mbox{\textit{CAIE M1 2023 Q4 [7]}}