Charge Density Calculator: Linear, Surface, and ...
Calculate linear, surface, and volumetric charge density. Learn how charge distributions create electric fields and why charge density matters in electromagnetism.
What is Charge Density?
Charge density describes how much electric charge is distributed per unit length, area, or volume of an object. It is fundamental to electrostatics and used to calculate electric fields via Gauss's law. There are three types: linear (λ), surface (σ), and volumetric (ρ).
⚡ Charge Density Calculator
Use our free calculator for instant, accurate results.
📐 Formula
λ = Q/L | σ = Q/A | ρ = Q/V
λ in C/m (wires), σ in C/m² (plates), ρ in C/m³ (solid objects). Q = total charge in Coulombs.
📝 Worked Example
A charged sphere of radius 0.1 m carries Q = 5 nC:
Surface charge density σ = Q/A = 5×10⁻⁹ / (4π×0.01)
σ ≈ 3.98 × 10⁻⁷ C/m²
📝 How to Use the Calculator
❓ FAQ
What is the unit of surface charge density?
C/m² (Coulombs per square meter). It can also be expressed as μC/cm².
How is charge density used in Gauss's law?
Gauss's law (∮E·dA = Q_enc/ε₀) uses enclosed charge, which is derived from integrating charge density over the enclosed volume.
Veer Kumavat
Founder & AuthorVeer is a 14-year-old student from Nashik, Maharashtra, who built SciFi Calculators to help students worldwide master STEM subjects. He is passionate about making complex science and math problems accessible through intuitive digital tools.