(peak) emf

Definition

Peak electromotive force (emf) is the maximum voltage generated in an AC generator during one cycle. It occurs when the rate of change of magnetic flux through the coil is at its highest.

5 Must Know Facts For Your Next Test

1. The peak emf is directly proportional to the number of turns in the coil, the area of the coil, and the angular velocity of rotation.
2. The peak emf can be calculated using $\varepsilon_{0} = NAB\omega$, where $N$ is the number of turns, $A$ is the area, $B$ is the magnetic field strength, and $\omega$ is angular velocity.
3. It occurs when the plane of the coil is perpendicular to the magnetic field lines.
4. Peak emf in a sinusoidal AC circuit corresponds to specific points on a sine wave graph where voltage reaches its maximum positive or negative value.
5. The root mean square (RMS) value of an AC voltage can be related to peak emf by $V_{rms} = \frac{V_{peak}}{\sqrt{2}}$.

Review Questions

Related terms

Electromagnetic Induction:

The process by which a changing magnetic field within a closed loop induces an electric current.

Angular Velocity:

The rate at which an object rotates around a specific point or axis; measured in radians per second.

Root Mean Square (RMS): A statistical measure used in physics to determine the effective or average value of an alternating current or voltage.