A railway truck with a mass of $8000\,\text{kg}$ is travelling at $1.0\,\text{m s}^{-1}$ towards the right. It then collides with a railway truck of mass $12000\,\text{kg}$ that is moving at $2.0\,\text{m s}^{-1}$ towards the left. After the impact, the two trucks are coupled together and continue moving as one. What is the velocity of the two trucks after the collision?
- A$1.6\,\text{m s}^{-1}$ to the left
- B$0.80\,\text{m s}^{-1}$ to the left
- C$0.80\,\text{m s}^{-1}$ to the right
- D$1.6\,\text{m s}^{-1}$ to the right