Magnetic field of an infinite straight current (B = μ₀I/(2πa))
jee-mainjee-advancedneet-ug
B = μ₀I/(2πa)
What each symbol means
| Symbol | What it stands for |
|---|---|
| B | Magnetic field magnitude at perpendicular distance a (T) |
| I | Steady current (A) |
| a | Perpendicular distance from wire to field point (m) |
| μ₀ | 4π×10⁻⁷ T·m/A |
When to use this
Infinitely long straight wire; steady current; vacuum/non-magnetic medium (replace μ₀ if needed).