Incandescent light bulbs use electrical energy to produce light energy, but it is not a direct transformation. Instead, the electrical energy is changed to a different form of energy, and then to light.
Electricity → ? → Light
What form of energy does the "?" represent?
SoundNo. Electrical energy can be transformed into sound energy, but that would not cause the bulb to light.
ThermalYes. As electrical energy flows through the filament, resistance changes the electrical energy into thermal energy. When the filament gets hot enough, some of the thermal energy is converted into light.
RadiationNo. The electrical energy is not transformed into radiation.
FrictionNo. The electrical energy is not transformed into friction.
Click to see which state standards this question tests, and which of my videos, experiments, and other resources support that topic.
SC.2.P.10.1 Discuss that people use electricity or other forms of energy to cook their food, cool or warm their homes, and power their cars.
SC.5.P.10.4 Investigate and explain that electrical energy can be transformed into heat, light, and sound energy, as well as the energy of motion.
UT.3.V.2.c Predict, measure, and graph the temperature changes produced by a variety of mechanical machines and electrical devices while they are operating.
4-PS3-4 Apply scientific ideas to design, test, and refine a device that converts energy from one form to another.
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