Two objects $X$ and $Y$ travel straight towards one another. The objects have equal mass. Object $X$ moves with a velocity of $5.0\,\text{m s}^{-1}$ to the right. Object $Y$ moves with a velocity of $3.0\,\text{m s}^{-1}$ to the left. Object $X$ and object $Y$ collide and remain stuck together. What is their velocity after the collision?
- A$1.0\,\text{m s}^{-1}$ to the left
- B$1.0\,\text{m s}^{-1}$ to the right
- C$4.0\,\text{m s}^{-1}$ to the left
- D$4.0\,\text{m s}^{-1}$ to the right