Question

The equatorial magnetic field of a magnetic dipole at a far distance r is:

Options

• \[B = \frac{\mu_0}{4\pi} \cdot \frac{m}{r^3}\]

• \[B = -\frac{\mu_0}{4\pi} \cdot \frac{2m}{r^3}\]

• \[B = \frac{\mu_0}{4\pi} \cdot \frac{2m}{r^3}\]

• \[B = -\frac{\mu_0}{4\pi} \cdot \frac{m}{r^3}\]

Answer 1

On the equatorial line, the magnetic dipole field is \(B = -\frac{\mu_0}{4\pi} \cdot \frac{m}{r^3}\), exactly mirroring the equatorial electric field \(E = -\frac{1}{4\pi\varepsilon_0} \cdot \frac{p}{r^3}\) with m replacing p and μ₀ replacing 1/ε₀.