A ball of mass $0.50\,\text{kg}$ drops and strikes the floor with a speed of $10\,\text{m s}^{-1}$. It then bounces back at $8.0\,\text{m s}^{-1}$, as shown. The impact between the ball and the floor takes $0.50\,\text{s}$. What average force acts on the ball while the collision occurs?
- A$2.0\,\text{N}$ upwards
- B$2.0\,\text{N}$ downwards
- C$18\,\text{N}$ upwards
- D$18\,\text{N}$ downwards