Final answer:
Adding energy to a system increases particle speed and thus raises its temperature. Conversely, removing energy decreases the temperature by lowering particle speed. The law of conservation of energy states that energy is neither created nor destroyed.
Step-by-step explanation:
Understanding Energy and Systems
If you add energy to a system, the particle speed typically increases. This relates to the kinetic energy of the particles: as energy is added, the kinetic energy increases, leading to faster particle motion.
If you remove energy from a system, the temperature usually decreases. This is because temperature is a measure of the average kinetic energy of the particles in a system, so reducing energy lowers their speed and thus the temperature.
Finally, the law of conservation of energy can be succinctly defined as: Energy cannot be created or destroyed.