The sentence starts out as such: Momentum and energy are only two of the many passive forces in the world. It is important to understand how momentum and energy function in a system to fully grasp their concepts and how the two forces affect and conserve themselves in a system. This lab was performed to learn how momentum is conserved during the collision, to understand how energy is conserved during the swing of the pendulum, and to develop the relationship between the two and their real-world application. I know that energy is not considered a force. So...., what could I put in place of passive forces? Also, please feel free to edit any other places in the paragraph as you see fit. Thank you!