How objects behave when they are moving back and forth, such as a person swinging on a swing.
A fundamental measurement in electricity.
Electricity is often described by the electric field.
Since electrostratic force is conservative, the concept of potential energy can be applied here.
Similar to how we had described the electric field as an invisible field that exists around every charge, the magnetic field is an invisible field that exists around magnetic particles.
Electricity and magnetism have a fundamental relationship with each other: magnetic fields are created by moving electric charge.