Using e in a Formula: Electric Potential

  • Thread starter Thread starter hardwork
  • Start date Start date
  • Tags Tags
    Formula
Click For Summary
SUMMARY

The discussion clarifies the use of the electron charge value in electric potential formulas, specifically whether to use +1.6x10^-19 C or -1.6x10^-19 C. It establishes that the electron carries a negative charge, thus the correct value to use in calculations involving work done by the electric force is -1.6x10^-19 C. The work done by the electric force when an electron moves from point c to point a is calculated as -1.1x10^-13 J, confirming that the magnitude of work remains the same regardless of the charge's perspective.

PREREQUISITES
  • Understanding of electric potential and voltage differences
  • Familiarity with the concept of electric charge, specifically the charge of an electron
  • Basic knowledge of work-energy principles in physics
  • Ability to perform calculations involving scientific notation
NEXT STEPS
  • Study the principles of electric potential and how it relates to electric fields
  • Learn about the work-energy theorem in the context of charged particles
  • Explore the implications of charge polarity in electric force calculations
  • Investigate the concept of potential difference and its applications in circuit analysis
USEFUL FOR

Physics students, electrical engineers, and anyone interested in understanding the behavior of charged particles in electric fields.

hardwork
Messages
20
Reaction score
0
When using e (for electron) in a formula, do you use +1.6x10^-19 C or -1.6x10^-19 C?

For example:

http://i44.tinypic.com/25g9te8.jpg

An electron moved from c to a. How much work is done by the electric force?

Electric Potential
Point a = 6.2x10^5 V
Point c = -7.5x10^4 V

Work = (-1.6x10^-19 C) (Va - Vc) = -1.1x10^-13
-W(electric force) = +1.1 x 10^-13

OR

Work = (1.6x10^-19 C) (Va - Vc) = 1.1x10^-13
-W(electric force) = -1.1 x 10^-13
 
Physics news on Phys.org
Welcome to PF.

Electron carries a negative charge.
 
According to the definition of the potential difference between the two points, it is the work done on the positive charge to move it against the electric force.
So the magnitude of the work is the same. Only difference is whether it is on the charge or by the charge.
 

Similar threads

Potential difference between two points in an electric field
  • · Replies 1 ·
Replies
1
Views
2K
Electric Field Strength - Assignment Question
  • · Replies 4 ·
Replies
4
Views
2K
Calculating the number of electrons given the force of repulsion
  • · Replies 5 ·
Replies
5
Views
4K
Photoelectric effect calculation
  • · Replies 8 ·
Replies
8
Views
3K
Electric potential due to shell containing a charge at an offset outside
  • · Replies 5 ·
Replies
5
Views
1K
How do you find electric field given only time and distance?
  • · Replies 1 ·
Replies
1
Views
2K
Electron move through capacitor
  • · Replies 3 ·
Replies
3
Views
2K
Why Is Work Positive When Done Against the Electric Field?
  • · Replies 22 ·
Replies
22
Views
4K
Calculating Charge of an Electron w/ the Millikan Oil Drop Experiment
  • · Replies 12 ·
Replies
12
Views
3K
Accelerated Electron and its Potential Energy
  • · Replies 5 ·
Replies
5
Views
2K