Question

wavelength in physical turns

Answer 1

Do you mean “turns” as full phase cycles (one full 360°/2π‑rad rotation) along space, or do you mean physical windings/turns of a helix/coil? They are related but used differently. A quick summary of both interpretations and the basic conversions:

If “turn” = one full cycle (one full phase rotation)
- Wavelength λ is the distance of one turn/cycle in space.
- Number of turns (cycles) in a physical length L:
N = L / λ
- Turns per unit length (spatial frequency, cycles per metre):
n = 1 / λ (cycles/m)
- Phase change per unit length:
in radians: k = 2π / λ (rad/m)
in degrees: 360° / λ (°/m)
- Phase at distance x from a reference:
φ(x) = 2π x / λ (radians) = 360° x / λ

Examples:
- If λ = 0.5 m, over L = 2 m you have N = 2 / 0.5 = 4 turns.
- For λ = 0.1 m, k = 2π/0.1 = 20π ≈ 62.83 rad/m.

If “turn” = physical winding of a helix/coil
- Number of turns on an axial length L for a helix with pitch p (distance between successive turns along axis):
N = L / p
- For helical antennas the relation between helix geometry and the electromagnetic wavelength depends on mode (axial vs normal). Typical design rules (axial mode): circumference C ≈ λ and pitch angle and pitch p chosen so the antenna radiates efficiently — but the simple length/turn relations above still apply for counting windings.

If you tell me which meaning you intend and give any numeric values (λ, L, pitch p, etc.), I can convert or compute what you need.