Energy Density of Fields Calculator
Calculate energy density stored in electric and magnetic fields using electromagnetic field theory
Calculate Energy Density
Electric field strength in the medium
Magnetic flux density in the medium
Select the material/medium
Select desired unit for energy density output
Energy Density Results
Energy Density Analysis
Example Calculation
Electromagnetic Wave
Electric Field: 2,000 N/C
Magnetic Field: 6.67 × 10⁻⁶ T
Medium: Vacuum
Calculation
uₑ = (ε₀/2)E² = (8.854×10⁻¹²/2)×(2×10³)²
uₘ = B²/(2μ₀) = (6.67×10⁻⁶)²/(2×4π×10⁻⁷)
Total: 1.77 × 10⁻⁵ J/m³
Key Formulas
uₑ = (ε/2)E²
Electric field energy density
ε = permittivity of medium
uₘ = B²/(2μ)
Magnetic field energy density
μ = permeability of medium
u = uₑ + uₘ
Total energy density
Sum of electric and magnetic components
Physical Constants
Understanding Energy Density of Fields
What is Energy Density?
Energy density is the amount of energy stored per unit volume in a medium. Electric and magnetic fields can store energy, which is fundamental to understanding electromagnetic waves, capacitors, inductors, and many other electromagnetic phenomena.
Types of Field Energy
- •Electric Field Energy: Stored in capacitors, around charged objects
- •Magnetic Field Energy: Stored in inductors, around magnets and currents
- •Electromagnetic Waves: Light, radio waves contain both types
Mathematical Foundation
u = (ε/2)E² + B²/(2μ)
Total energy density formula
Note: Energy density behaves like pressure - it exerts force on boundaries and can drive electromagnetic phenomena.
Electromagnetic Waves
In electromagnetic waves (like light), energy oscillates between electric and magnetic forms. The total energy density determines the intensity of the wave.
Capacitors & Inductors
Capacitors store energy in electric fields between plates. Inductors store energy in magnetic fields around coils. Both are essential components in electronics.
Practical Applications
Understanding field energy density is crucial for designing antennas, MRI machines, particle accelerators, and energy storage systems.