Voltage/Potential Difference

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In summary, voltage is also referred to as potential difference because it is related to the difference in electrical potential or pressure that causes electric charge to move in a circuit. It can be calculated by measuring the difference in electrical pressure applied to the two ends of a circuit. Additionally, voltage can be compared to the pressure in a fluid circuit, where the movement of water depends on the difference in pressure applied. The concept of voltage has evolved over time, with "electrical pressure" being replaced by "electrical potential" and eventually shortened to "potential difference."
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Why is voltage also called potential difference? And what is the 'push' on the electrons, and how can this be calculated?

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FeDeX_LaTeX said:

Why is voltage also called potential difference? And what is the 'push' on the electrons, and how can this be calculated?


The terms met with in electricity have some historical bias. Voltage appears to come from the name of the scientist Alessandro Giuseppe Antonio Anastasio Volta who was one of the first people to investigate electric circuits (http://en.wikipedia.org/wiki/Alessandro_Volta)

One way to introduce the linke between voltage and currents in an electric circuit is to make an analogy between water flowing in a pipe (a "fluid circuit").

The rate at which electric charge (or current) moves around a circuit depends in part on the "electrical pressure" provided by a battery. In fact, it is the "difference in electrical pressure" that is applied to the two ends of the circuit that is important.

People usually say objects move because there is a force acting on them. In fact, it is probably more accurate to say is the difference in forces that make objects move.

To get to p.d. make the following steps:
1) "difference in electrical pressure" -> "difference in electrical potential"
2) "difference in electrical potential" -> "electrical potential difference"
3) "electrical potential difference" -> "potential difference"

There is possibly a historical reason why "electrical pressure" becomes "electrical potential".

Electric charge moves (i.e. an electric current flows) because of differences in the electrical forces acting on it. I usually try to say a current flows through a component because there is a difference in electrical potential on the two sides of the component, i.e. a current flows because of a p.d.

1. What is voltage/potential difference?

Voltage or potential difference is a measure of the electric potential energy per unit charge between two points in an electric circuit. It is the driving force that pushes electric charges through a conductor.

2. How is voltage/potential difference measured?

Voltage is measured in volts (V) using a voltmeter. It is connected in parallel to the two points in the circuit where the potential difference is being measured.

3. What causes a difference in voltage/potential difference?

Voltage or potential difference is caused by the difference in electric potential energy between two points in a circuit. This difference can be created by a battery or power source, which provides the energy to move electric charges.

4. What is the relationship between voltage and current?

Ohm's law states that the current flowing through a conductor is directly proportional to the voltage applied across it, and inversely proportional to its resistance. This means that an increase in voltage will result in an increase in current, while an increase in resistance will result in a decrease in current.

5. What are the practical applications of understanding voltage/potential difference?

Understanding voltage/potential difference is essential in designing and troubleshooting electrical circuits, as well as in the production and distribution of electricity. It is also important in understanding the functioning of electronic devices such as computers, televisions, and smartphones.