Electric Circuits - Mission EC2 Detailed Help

The role of the battery in an electrical circuit is to ____. List all that apply ... 


 
The Role of a Battery:
The role of a battery (or cell) in an electric circuit is to supply energy to the circuit by doing work upon the charge to move it from the low energy terminal to the high energy terminal. By moving charge to high energy, the battery (or cell) is establishing a difference in electric potential across the two ends of the external circuit. With this difference in electric potential established, charge will spontaneously flow through the external circuit.


 
In a sense, circuits are all about energy. Energy is introduced into the circuit by the battery. The battery acts as a charge pump in a circuit, serving the same role as a water pump in a water circuit. The battery moves the charge from low energy to high energy much like a water pump moves water from low energy to high energy. Both processes require the input of energy to the system. If the battery is the energy input location of a circuit, then the energy output is the motor or the light bulb or the sound amplifier or the ... . In this sense, circuits are all about energy and the battery is the pump that makes it all possible.


 
Some students of physics have the incorrect conception that a battery's role is to supply the electrons or the protons that move through a circuit. Their thought is that when a battery no longer works, it is out of protons or electrons. After all, the battery must be recharged to work again. But don't be fooled! Batteries do not supply charge to a circuit. And the use of the phrases rechargeable and recharged are unfortunate misnomers. A battery is actually being re-energized rather than recharged. It's energy-producing ability are being restored by the reversing of the chemical reaction that occurs inside. See Think About It section.