Coulomb's Law Simulator
Classroom worksheet · Interactive simulation: https://lkforge.com/tools/physics/coulombs-law/
Name: Date:
Learning objectives
- Apply Coulomb’s law to the force between charges.
- Describe how force depends on charge and separation.
- Compare attractive and repulsive interactions.
Variables to change
- Charge magnitudes
- Charge signs
- Separation distance
Procedure
- Place two like charges and note the force.
- Double one charge and observe the force.
- Double the separation and observe the force.
- Switch one charge’s sign and note the direction change.
Observations
Record the force as you change charge magnitude, separation, and sign.
Questions
- Write Coulomb’s law.
- What happened to the force when you doubled the separation?
- What happened when you doubled one charge?
- How do like and unlike charges interact?
- How is Coulomb’s law similar to Newton’s law of gravitation?
Answer key (instructors)
- 1. F = k·q₁·q₂/r², with k ≈ 8.99×10⁹ N·m²/C².
- 2. It dropped to one quarter — the force is inverse-square in distance.
- 3. The force doubled — it is proportional to each charge.
- 4. Like charges repel; unlike charges attract.
- 5. Both are inverse-square laws; Coulomb’s can attract or repel, while gravity only attracts.
Coulomb’s law F = k·q₁q₂/r² gives the electrostatic force: proportional to each charge and inverse-square in separation. Like charges repel, unlike attract — the same inverse-square form as gravity, but two-signed.