| Exam Board | OCR |
|---|---|
| Module | M2 (Mechanics 2) |
| Year | 2009 |
| Session | June |
| Marks | 8 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Power and driving force |
| Type | Maximum speed on incline vs horizontal |
| Difficulty | Standard +0.3 This is a straightforward M2 power question requiring standard application of P=Fv and F=ma with resistance forces. Part (i) is routine (P=Fv with resistance only), part (ii) adds a component force down the slope, and part (iii) requires resolving forces and finding acceleration. All steps follow standard procedures with no novel problem-solving required, making it slightly easier than average. |
| Spec | 3.03v Motion on rough surface: including inclined planes6.02l Power and velocity: P = Fv6.02m Variable force power: using scalar product |
2 A car of mass 1100 kg has maximum power of 44000 W . The resistive forces have constant magnitude 1400 N .\\
(i) Calculate the maximum steady speed of the car on the level.
The car is moving on a hill of constant inclination $\alpha$ to the horizontal, where $\sin \alpha = 0.05$.\\
(ii) Calculate the maximum steady speed of the car when ascending the hill.\\
(iii) Calculate the acceleration of the car when it is descending the hill at a speed of $10 \mathrm {~m} \mathrm {~s} ^ { - 1 }$ working at half the maximum power.
\hfill \mbox{\textit{OCR M2 2009 Q2 [8]}}