M2 June 2011 Q1
1. A car of mass 1000 kg moves with constant speed \(V\) m s\(^{-1}\) up a straight road inclined at an angle \(\theta\) to the horizontal, where \(\sin\theta = \dfrac{1}{30}\). The engine of the car is working at a rate of 12 kW. The resistance to motion from non-gravitational forces has magnitude 500 N.
Find the value of \(V\). (5)

| Scheme | Marks |
|---|---|
| \(12000 = TV\) | M1 |
| \(T - 500 - 1000g\sin\theta = 0\) | M1 A1 |
| \(V = \dfrac{12000}{500 + 1000 \times 9.8 \times \frac{1}{30}}\) | |
| \(V = 15\quad\) (accept 14.5) | DM1 A1 |
| (5 marks) |