Magnetic Field (Wire) Calculator
Calculate the magnetic field around a current-carrying wire.
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Enter the current flowing through the wire and the perpendicular distance from the wire. The calculator computes the magnetic field in both tesla and gauss.
About Magnetic Field (Wire)
Every current-carrying conductor generates a magnetic field. For a long straight wire, the field at distance r equals mu_0 times current divided by (2 pi r), where mu_0 is the permeability of free space. The field forms concentric circles around the wire, with direction given by the right-hand rule. This relationship is fundamental to electromagnetism, motors, transformers, and electromagnetic shielding.
Frequently Asked Questions
What is the magnetic field around a wire?
A current-carrying wire produces a circular magnetic field around it. The field strength decreases with distance from the wire and is proportional to the current.
What is the right-hand rule?
Point your right thumb in the direction of current flow. Your fingers curl in the direction of the magnetic field lines, which form concentric circles around the wire.
What is mu_0?
mu_0 (permeability of free space) is a physical constant: 4 x pi x 10^-7 T m/A. It appears in all magnetic field calculations in vacuum or air.