Answer:
The law of conservation of energy says that the total energy of a system that is isolated is constant. So, in a battery-operated flashlight, we can see that the chemical energy of the battery is transformed into light. Therefore, the energy is not being created, it is just transformed into a new type. In the same way, the energy in the wood in a campfire is transformed into heat and light, so it is another way to demonstrated that the energy is conserved.
