The previous two activities in this module have shown us the importance of conservation laws. These laws provide extra “tools” that allow us to analyze certain aspects of physical systems and to be able to predict the motion of objects in the systems without using more complicated analysis. Even in situations wherein we cannot exactly solve the motion, these laws are incredibly useful. For instance, if someone shows us an incredibly complicated device that can seemingly produce electricity with no energy input whatsoever, we know not to invest money in this device, as it must be a sham since it violates the conservation of energy principle. However, both of these conservation laws are theoretical constructs that rarely, if ever, hold 100% true in the real world. The experiments that were run showed proof of this, as the experimental results did not match the theoretical model. Energy is lost as it is transferred from kinetic to potential, and vice-versa. Momentum was not conserved during the collisions, as they turned out to be neither perfectly elastic or perfectly inelastic. It turns out that there is another law at work that limits these other conservation laws: the Second Law of Thermodynamics.