Why is voltage called potential difference?

Click For Summary

Discussion Overview

The discussion centers around the terminology of "voltage" and its relationship to "potential difference," exploring the conceptual underpinnings of these terms in the context of electric circuits and potential energy.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants explain that "potential" refers to potential energy, drawing analogies between electric potential and gravitational potential energy.
  • One participant questions the use of "potential" by stating that there isn't a voltage before a circuit is switched on, suggesting a misunderstanding of the term.
  • Another participant asserts that "potential difference" is synonymous with "voltage," emphasizing that a battery presents a potential difference when connected to a circuit.
  • A different viewpoint is introduced, suggesting that voltage can be thought of as pressure in a water pipe, indicating that voltage exists even when there is no current flow.

Areas of Agreement / Disagreement

Participants express differing views on the concept of potential in relation to voltage, with some agreeing on the definitions while others challenge the applicability of the term "potential" in certain scenarios. The discussion remains unresolved regarding the interpretation of voltage and potential difference.

Contextual Notes

There are varying interpretations of the presence of voltage in circuits, particularly concerning open circuits and the conditions under which potential difference is recognized. The discussion reflects differing assumptions about the nature of voltage and potential energy.

Jack
Messages
107
Reaction score
0
Why is voltage called potential difference?
 
Physics news on Phys.org
"Potential" refers to potential energy -- for example, a test charge at rest in an electric field has potential energy. In a similar way, a brick held in the air has gravitational potential energy.

Between two points at different heights above the ground, there is a difference in potential. Between two points in a circuit with different voltages, there is a difference in potential. A voltage is a difference in potential, or a potential difference.

- Warren
 
Originally posted by chroot
"Potential" refers to potential energy -- for example, a test charge at rest in an electric field has potential energy. In a similar way, a brick held in the air has gravitational potential energy.

Between two points at different heights above the ground, there is a difference in potential. Between two points in a circuit with different voltages, there is a difference in potential. A voltage is a difference in potential, or a potential difference.

- Warren

But it's not potential is it because there isn't a voltage before you switch the circuit on. If this statement is wrong then I still don't understand and then could someone else please try explaining it to me.
 
Originally posted by Jack
But it's not potential is it because there isn't a voltage before you switch the circuit on. If this statement is wrong then I still don't understand and then could someone else please try explaining it to me.
If there's no voltage, then there is no potential difference, that's correct. "Potential difference" is synonymous with "voltage."

The two ends of a AA battery have two different electric potentials; therefore, the battery presents a potential difference (or voltage). When you connect it to a circuit, the potential difference coaxes charges to move.

In a similar manner, when you let go of the brick you're holding in mid-air, the brick is coaxed to move by the difference in gravitational potential.

- Warren
 
But it's not potential is it because there isn't a voltage before you switch the circuit on.

The fact is circiut source voltage is present across an open switch. The way to find an open in a live circiut is to measure voltages, looking for a wire or connection that measure source voltage.

There is your potetial.
 
Try thinking of it as pressure. A good analogy is water in a pipe. Voltage is the pressure whether the switch or valve is open or not. Current or amperage is the amount of water or electrons that flow. Obvisously when the switch is open there is no current flow but the pressure i.e. voltage/potenial is still there.
 

Similar threads

Undergrad When to properly use "voltage"
  • · Replies 25 ·
Replies
25
Views
2K
Undergrad Electric potential and potential difference
  • · Replies 7 ·
Replies
7
Views
3K
Undergrad How is Potential Difference Created across a Resistor?
  • · Replies 21 ·
Replies
21
Views
5K
Undergrad Electric Potential in circuit
  • · Replies 3 ·
Replies
3
Views
1K
High School Some Questions about Electric Current/Capacitors to help my understanding
  • · Replies 7 ·
Replies
7
Views
3K
Undergrad Potential difference between a battery's terminal and Earth ground
  • · Replies 58 ·
2
Replies
58
Views
6K
High School Understanding Voltage: How Potentials Differ & Flow
  • · Replies 10 ·
Replies
10
Views
2K
Undergrad Is electromotive force always equal to potential difference?
  • · Replies 9 ·
Replies
9
Views
2K
High School The voltage between two points
  • · Replies 11 ·
Replies
11
Views
2K
Undergrad How is Potential Difference Created in Electrolytes?
  • · Replies 10 ·
Replies
10
Views
1K