MCQ
$A$ spring block system is placed on a rough horizontal floor. The block is pulled towards right to give spring an elongation less than $\frac{{2\mu mg}}{K}$ but more than $\frac{{\mu mg}}{K}$ and released. Which of the following laws/principles of physics can be applied on the spring block system


- Aconservation of mechanical energy
- Bconservation of momentum
- ✓work energy principle
- DNone


