| Exam Board | CAIE |
|---|---|
| Module | M1 (Mechanics 1) |
| Year | 2013 |
| Session | June |
| Marks | 4 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Friction |
| Type | Block on horizontal plane motion |
| Difficulty | Moderate -0.3 Part (i) requires basic conceptual understanding of friction (vertical force reduces normal reaction, making it easier to move the block). Part (ii) is a standard application of F=ma and friction laws with straightforward arithmetic. Both parts are routine M1 exercises requiring no problem-solving insight, though slightly easier than average due to the conceptual nature of part (i) and simple single-step calculation in part (ii). |
| Spec | 3.03u Static equilibrium: on rough surfaces3.03v Motion on rough surface: including inclined planes |
| Answer | Marks | Guidance |
|---|---|---|
| Answer/Working | Mark | Guidance |
| Less than | B1 | |
| \(F = 1.25W\) so \(W < F\) | B1 | [2] |
| Answer | Marks | Guidance |
|---|---|---|
| Answer/Working | Mark | Guidance |
| \([P - 60 \times 1.25 = 6 \times 4]\) | M1 | For applying Newton's second law |
| \(P = 99\) | A1 | [2] |
## Question 1:
### Part (i)
| Answer/Working | Mark | Guidance |
|---|---|---|
| Less than | B1 | |
| $F = 1.25W$ so $W < F$ | B1 | [2] |
### Part (ii)
| Answer/Working | Mark | Guidance |
|---|---|---|
| $[P - 60 \times 1.25 = 6 \times 4]$ | M1 | For applying Newton's second law |
| $P = 99$ | A1 | [2] |
---1 A block is at rest on a rough horizontal plane. The coefficient of friction between the block and the plane is 1.25 .\\
(i) State, giving a reason for your answer, whether the minimum vertical force required to move the block is greater or less than the minimum horizontal force required to move the block.
A horizontal force of continuously increasing magnitude $P \mathrm {~N}$ and fixed direction is applied to the block.\\
(ii) Given that the weight of the block is 60 N , find the value of $P$ when the acceleration of the block is $4 \mathrm {~m} \mathrm {~s} ^ { - 2 }$.
\hfill \mbox{\textit{CAIE M1 2013 Q1 [4]}}