CAPE Physics Unit 1 · 2011 · Paper 1 · Question Q9

A rocket in gravity-free space is burning 5.0 \times 10^2\text{ kg} of fuel per second. The exhaust gases are expelled at 8.0 \times 10^3\text{ m s}^{-1} relative to the rocket, whose mass is 2.0 \times 10^5\text{ kg} at that time. What is its acceleration?

1. (A)10\text{ m s}^{-2}
2. (B)20\text{ m s}^{-2}
3. (C)400\text{ m s}^{-2}
4. (D)2500\text{ m s}^{-2}