How to Calculate Electric Field
What is Electric Field?
Electric field strength measures the electric force per unit charge at a location. It's fundamental to electrostatics and electromagnet behavior.
Formula
The calculator applies E = kQ / r² for single charge, superposition for multiple
- E
- kQ / r² for single charge — kQ / r² for single charge
Step-by-Step Guide
- 1Enter the source charge and distance, or use field from multiple charges
- 2The calculator applies E = kQ / r² for single charge, superposition for multiple
- 3Results show electric field magnitude and direction
Worked Examples
Input
Q = 1 μC, r = 1 m
Result
E ≈ 8,990 V/m
Using k = 8.99 × 10⁹ N·m²/C²
Common Mistakes to Avoid
- ✕Forgetting to square the distance
- ✕Confusing electric field with electric potential
Frequently Asked Questions
Is electric field direction standardized?
By convention, electric field lines point away from positive charges and toward negative charges.
How do you combine multiple electric fields?
Use vector superposition; add field vectors from all sources, accounting for direction.
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