Electric and magnetic fields

Definition

Electric and magnetic fields are two interdependent fields that propagate as waves through space. They form the basis of electromagnetic waves, where oscillations in one field induce oscillations in the other.

5 Must Know Facts For Your Next Test

1. Electric and magnetic fields are perpendicular to each other and to the direction of wave propagation.
2. The speed of electromagnetic waves in a vacuum is approximately $3 \times 10^8$ meters per second (the speed of light).
3. Electromagnetic waves carry energy, which can be quantified by their intensity or power per unit area.
4. The strength of an electric field is measured in volts per meter (V/m), while the strength of a magnetic field is measured in teslas (T) or gauss (G).
5. Maxwell's equations describe how electric and magnetic fields are generated and altered by each other and charges.

Review Questions

• What is the relationship between electric and magnetic fields in an electromagnetic wave?
• How do you measure the strength of an electric field? How about a magnetic field?
• What do Maxwell's equations describe concerning electric and magnetic fields?

Related terms

Electromagnetic Wave: A wave consisting of oscillating electric and magnetic fields that propagate through space at the speed of light.

Maxwell's Equations:

A set of four fundamental equations that describe how electric charges produce electric fields, how currents produce magnetic fields, how changing magnetic fields produce electric fields, and how changing electric fields produce magnetic fields.

Intensity:

The power transferred per unit area, often used to quantify the amount of energy carried by an electromagnetic wave.