\[B=\frac{\mu_0 I}{2\pi r}\]
Variables
Bmagnetic field strength (T)
mu0vacuum permeability (H/m)
Ielectric current (A)
rdistance from the wire (m)
Description
What is this formula?
This formula calculates the magnetic field generated around a long straight current-carrying wire. The magnetic field forms concentric circles around the conductor.
When to use it
Use this equation when analyzing magnetic fields generated by electrical currents in conductors, transmission lines, and electromagnetic devices.
Example
A straight wire carries a current of 15 A. Calculate the magnetic field at a distance of 0.08 m from the wire.
Data:
I = 15 A
r = 0.08 m
mu0 = 4*pi*10^-7 H/m
Formula:
B = (mu0*I)/(2*pi*r)
Substitution:
B = ((4*pi*10^-7)*15)/(2*pi*0.08)
Result:
B = 3.75 × 10^-5 T
Applications
- Electromagnetic field analysis
- Power transmission systems
- Electric motor design
- Magnetic sensor calculations
- Electrical engineering