Voltage and the concept of work

In summary, voltage is the work done per unit of charge from the electric field to move a charge from one point to another. Work is done on a charge by moving it in opposition to an electric field, causing the charge to gain energy. In the case of a battery, work is done by a chemical reaction on ions inside the battery, causing electrons in the external circuit to move from the negative terminal to the positive terminal. This work is powered by the chemical potential energy of two or more chemicals that react when placed together.
  • #1
user111_23
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Okay, I understand that voltage is the work done per unit of charge from the electric field to move a charge from one point to another.

What does it mean for work being done on a charge? Are the charges being moved by an electric field? If so, why would the electrons move towards the negative terminal in a battery? Why not the positive terminal? (Since + goes with -.)
 
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  • #2
To do work on a charge, we have to move it in opposition to an electric field. We do work, the charge gains energy.

In the case of a battery, electrons in the external circuit move spontaneously from the negative terminal to the positive terminal. Ions inside the battery complete the circuit, driven by a chemical reaction that performs work on the ions.
 
  • #3
Mapes said:
To do work on a charge, we have to move it in opposition to an electric field. We do work, the charge gains energy.

In the case of a battery, electrons in the external circuit move spontaneously from the negative terminal to the positive terminal. Ions inside the battery complete the circuit, driven by a chemical reaction that performs work on the ions.

I understand that. However, where is work coming from? What causing work to be done on the charge?
 
  • #4
The work comes from the chemical potential energy of two or more chemicals that are not at equilibrium and react when placed together.
 
  • #5
Mapes said:
The work comes from the chemical potential energy of two or more chemicals that are not at equilibrium and react when placed together.

Ah that makes sense. Thanks!
 

1. What is voltage?

Voltage is the measure of electrical potential energy per unit charge. It is commonly referred to as the "pressure" or "force" that pushes electrons through a conductor.

2. How is voltage measured?

Voltage is typically measured in units of volts (V) using a voltmeter. It can also be calculated by dividing the amount of electrical energy by the amount of charge.

3. What is the relationship between voltage and current?

Voltage and current have a direct relationship, meaning that as voltage increases, so does current. This is known as Ohm's Law, which states that the current through a conductor is directly proportional to the voltage and inversely proportional to the resistance.

4. How does voltage relate to the concept of work?

Work is defined as the transfer of energy. In the case of voltage, it is the work done to move electrons from one point to another. The higher the voltage, the more work is required to move the electrons, and therefore, the greater the energy transfer.

5. What are some common sources of voltage?

There are many sources of voltage, including batteries, power plants, and generators. Other sources include solar panels, wind turbines, and fuel cells. In everyday life, we also encounter voltage in outlets and electronic devices that require electricity to function.

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