\[U=\frac{k q_1 q_2}{r}\]
Variables
UCoulomb potential energy (J)
kCoulomb constant (N·m²/C²)
q1first electric charge (C)
q2second electric charge (C)
rdistance between charges (m)
Description
What is this formula?
The Coulomb potential energy formula calculates the electric potential energy between two point charges separated by a distance.
When to use it
Use this formula in electrostatics, chemical physics, atomic physics, and molecular interaction analysis when modeling the energy associated with two charged particles.
Example
Two charges have:
q1 = 2.0×10^-6 C
q2 = -3.0×10^-6 C
r = 0.50 m
Using:
k = 8.99×10^9 N·m²/C²
Formula:
U = k*q1*q2/r
Substitution:
U = 8.99×10^9 × 2.0×10^-6 × (-3.0×10^-6) / 0.50
Result:
U ≈ -0.108 J
The Coulomb potential energy is approximately -0.108 J.
Applications
- Electrostatic interactions
- Ionic bonding models
- Atomic and molecular physics
- Plasma physics
- Charged particle systems