Magnetic field strength at the center of a circular loop

Definition

Magnetic field strength at the center of a circular loop is the intensity of the magnetic field produced by a current-carrying wire loop at its geometric center. It depends on the current flowing through the loop and its radius.

5 Must Know Facts For Your Next Test

1. The magnetic field strength at the center of a circular loop is given by $B = \frac{\mu_0 I}{2R}$, where $B$ is the magnetic field strength, $\mu_0$ is the permeability of free space, $I$ is the current, and $R$ is the radius of the loop.
2. The direction of the magnetic field at the center of a circular loop follows the right-hand rule: if you curl your fingers in the direction of current flow, your thumb points in the direction of the magnetic field.
3. As current increases or radius decreases, magnetic field strength increases proportionally.
4. A single loop produces a weaker magnetic field compared to multiple closely packed loops (a coil or solenoid).
5. Magnetic fields produced by different segments of a circular loop add up vectorially at its center.

Review Questions

• What formula is used to calculate the magnetic field strength at the center of a circular loop?
• How does increasing the current through a circular loop affect its central magnetic field?
• What rule determines the direction of the magnetic field in relation to current flow in a circular loop?

Related terms

Ampere's Law: A fundamental law stating that for any closed-loop path, the sum of lengths times their corresponding magnetic fields equals μ₀ times enclosed current.

Permeability: A measure of how easily a material can support a magnetic field within itself, denoted as μ₀ for free space.

Right-Hand Rule: A mnemonic for determining directions in electromagnetism: point your thumb in direction of current; curled fingers show direction of induced magnetic fields.