Maxwell’s equations are a set of four fundamental laws that describe how electric and magnetic fields behave and interact. Formulated by James Clerk Maxwell in the 19th century, they form the core of classical electromagnetism, explaining everything from how light travels to how electric motors work.
What Do Maxwell’s Equations Describe?
- Electric Fields and Charges
Electric fields originate from electric charges. Positive charges create outward field lines, while negative charges attract them inward. - Magnetic Fields and No Monopoles
Unlike electric charges, magnetic poles always come in pairs—north and south. There are no known magnetic monopoles, so magnetic field lines always form closed loops. - Changing Magnetic Fields Create Electric Fields
A time-varying magnetic field generates an electric field. This is the principle behind electric generators and transformers. - Changing Electric Fields Create Magnetic Fields
Similarly, a changing electric field produces a magnetic field. This dynamic is key to the propagation of electromagnetic waves, like light and radio waves.
Significance of Maxwell’s Work:
- Maxwell unified electricity, magnetism, and optics into a single framework.
- His equations predicted that light is an electromagnetic wave, traveling through space at a constant speed—the speed of light.
- These equations laid the groundwork for technologies like radio, radar, wireless communication, and modern electrical engineering.