Physics » Electromagnetic Induction and AC Circuits » Induced Emf and Magnetic Flux

# Summarizing Induced Emf and Magnetic Flux

## Summary

• The crucial quantity in induction is magnetic flux $$\Phi$$, defined to be $$\Phi =\text{BA}\phantom{\rule{0.25em}{0ex}}\text{cos}\phantom{\rule{0.25em}{0ex}}\theta$$, where $$B$$ is the magnetic field strength over an area $$A$$ at an angle $$\theta$$ with the perpendicular to the area.
• Units of magnetic flux $$\Phi$$ are $$\text{T}\cdot {\text{m}}^{2}$$.
• Any change in magnetic flux $$\Phi$$ induces an emf—the process is defined to be electromagnetic induction.

## Glossary

### magnetic flux

the amount of magnetic field going through a particular area, calculated with $$\Phi =\text{BA}\phantom{\rule{0.25em}{0ex}}\text{cos}\phantom{\rule{0.25em}{0ex}}\theta$$ where $$B$$ is the magnetic field strength over an area $$A$$ at an angle $$\theta$$ with the perpendicular to the area

### electromagnetic induction

the process of inducing an emf (voltage) with a change in magnetic flux