find the magnetic field a distance r from the center of a long wire that has radius a and carries a uniform current per unit area j in the positive z direction.
What is the formula to find the magnetic field a distance r from the center of a long wire with radius a carrying a uniform current per unit area j in the positive z direction?
Answer:
To find the magnetic field at a distance r from the center of a long wire with radius a and carrying a uniform current per unit area j in the positive z direction, you can use Ampère’s circuital law. The formula to calculate the magnetic field is given by:
B = \frac{\mu_0 \cdot j \cdot r}{2}
Where:
- B is the magnetic field intensity,
- \mu_0 is the permeability of free space (4\pi \times 10^{-7} T \cdot m/A),
- j is the current density,
- r is the radial distance from the center of the wire.