A fan spins in a small room. The system encompasses the fan itself, the source of electricity, and the ambient air. Which choice best describes the primary energy transformations that occur within this system? The thermal energy in the room appears to boost the electrical energy supplied to the fan, which seems to make the fan work better and spin faster. As the fan operates, it directly turns the electrical energy into thermal energy in the blades, which causes the blades to heat up quite a bit. The fan's motor changes the electrical energy into the kinetic energy that spins the blades.