How to Calculate Magnetic Field Wire
What is Magnetic Field Wire?
Magnetic field from a current-carrying wire follows the right-hand rule. It's fundamental to electromagnets, motors, and induction devices.
Formula
The calculator applies B = (μ × I) / (2π × r)
- B
- (μ × I) / (2π × r) — (μ × I) / (2π × r)
- I
- I value — Variable used in the calculation
Step-by-Step Guide
- 1Enter current, distance from wire, and relative permeability
- 2The calculator applies B = (μ × I) / (2π × r)
- 3Results show magnetic field strength in tesla
Worked Examples
Input
I = 10 A, r = 0.01 m (1 cm)
Result
B ≈ 200 μT
Comparable to Earth's magnetic field
Common Mistakes to Avoid
- ✕Forgetting to convert current to amperes
- ✕Confusing field direction with current direction
Frequently Asked Questions
Does current direction affect field direction?
Yes, use the right-hand rule: thumb points along current, fingers curl in field direction.
Why does field decrease with distance?
Field spreads in a cylindrical pattern; area increases linearly with radius, reducing field density.
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