The key difference lies in what causes them and how they interact with charged particles: electric force acts on all charged particles regardless of their motion, while magnetic force only acts on moving charged particles.
Here's a breakdown:
Electric Force
- Source: All charged particles (whether moving or stationary) create an electric field that exerts an electric force on other charged particles.
- Interaction: Electric force acts on charged particles regardless of whether they are moving or stationary.
- Direction: The electric force acts parallel (or anti-parallel, depending on the sign of the charge) to the electric field. A positive charge will experience a force in the direction of the electric field, and a negative charge will experience a force in the opposite direction.
Magnetic Field
- Source: Magnetic fields are created by moving electric charges (electric current). This can be in the form of electrons moving through a wire, or charged particles moving through space.
- Interaction: Magnetic force only acts on moving charged particles. A stationary charge will not experience a magnetic force.
- Direction: The magnetic force acts perpendicular to both the velocity of the charged particle and the magnetic field. This is described by the right-hand rule, where your thumb points in the direction of the particle's velocity, your fingers point in the direction of the magnetic field, and the force is directed out of your palm (for a positive charge).
Key Differences Summarized in a Table:
| Feature | Electric Force | Magnetic Force |
|---|---|---|
| Source | Any charged particle (moving or not) | Moving charged particles (electric current) |
| Acts on | Any charged particle (moving or not) | Only moving charged particles |
| Direction | Parallel/anti-parallel to the field | Perpendicular to both velocity and field |
Example
Imagine a stationary electron sitting in space. It will experience an electric force if placed within an electric field. However, it will not experience a magnetic force unless a magnetic field is present and the electron starts to move. Once it is moving, it will be affected by the magnetic field.
In essence, the electric force is a fundamental force that exists between any two charged objects, regardless of their motion. The magnetic force is a force that arises due to the movement of electric charges, and it only affects other moving charges.
