Skip to content

Physical Properties of Coil Calculator

This calculator determines key physical characteristics of a coil, such as total wire length, weight, resistance, and turns per unit length, based on wire diameter, coil dimensions, and material type. It’s useful for coil winding, transformer design, and inductive component prototyping.

Coil Geometry and Material Properties Estimator

Input Fields
N
Total number of turns
D
mm
Diameter of the coil (mean turn diameter)
d
mm
Diameter of the wire
If enabled, the result will update automatically when you change any value.

Physical Coil Formulas

Formula
$$l = N \cdot \pi \cdot D$$ $$R = \rho \cdot \frac{l}{A}$$ $$m = l \cdot \gamma$$ $$n = \frac{N}{L}$$

Where:

  • $$l$$ = total wire length (m)
  • $$N$$ = number of turns
  • $$D$$ = average diameter of the coil (m)
  • $$A$$ = cross-sectional area of wire (m²)
  • $$\rho$$ = resistivity of conductor (Ω·m)
  • $$R$$ = wire resistance (Ω)
  • $$m$$ = wire mass (kg)
  • $$\gamma$$ = density of conductor material (kg/m)
  • $$n$$ = turns per meter
  • $$L$$ = length of the coil (m)


Physical Properties of Coil – Calculation Example

Given:

  • $$N$$ = 200 turns
  • $$D$$ = 0.04 m
  • $$wire diameter d$$ = 0.5 mm = 0.0005 m
  • $$\rho (copper)$$ = $$1.68 × 10^{-8} Ω·m$$
  • $$\gamma (copper)$$ = $$8.96 × 10^3 kg/m³$$
  • $$L$$ = 0.1 m

Calculation:

  1. $$l = 200 \cdot \pi \cdot 0.04 ≈ 25.13~m $$
  2. $$A = \pi \cdot \left( \frac{0.0005}{2} \right)^2 ≈ 1.96 \cdot 10^{-7}~\text{m}^2 $$
  3. $$R = 1.68 \cdot 10^{-8} \cdot \frac{25.13}{1.96 \cdot 10^{-7}} ≈ 2.15~Ω $$
  4. $$\gamma_{\text{linear}} = \gamma \cdot A = 8.96 \cdot 10^3 \cdot 1.96 \cdot 10^{-7} ≈ 1.75~\text{kg/m}$$
  5. $$m = 25.13 \cdot 1.75 ≈ 43.97~\text{g} $$
  6. $$n = \frac{200}{0.1} = 2000~\text{turns/m}$$


Understanding the physical properties of a coil is essential when designing inductors, transformers, electromagnets, or RF coils. This calculator helps estimate wire length, resistance, and weight before winding, allowing for precise material planning and thermal/electrical efficiency assessment. It supports different conductor materials by adjusting resistivity and density values, making it ideal for practical engineering and educational use.

Previous
PI Network Impedance Matching

Leave a Reply

Your email address will not be published. Required fields are marked *