Question

What is an example of hysteresis in electricity?

Answer 1

An example of hysteresis in electricity is found in **magnetic materials** like **ferromagnetic materials** (e.g., iron).

Here's how it works:

1. When a magnetic field is applied to a ferromagnetic material, the material becomes magnetized. As the magnetic field increases, the material’s magnetization increases as well.
   
2. If the magnetic field is then reduced, the material does not lose its magnetization immediately. Instead, it retains some magnetization even when the external magnetic field is zero. This is called **remanent magnetization**.

3. If the magnetic field is reversed, the material’s magnetization will eventually decrease, but the rate at which it changes is not the same as when the field was increasing. This creates a **loop** when you plot the magnetization of the material against the magnetic field strength.

This loop is called the **hysteresis loop**. The difference between the path of increasing and decreasing the magnetic field is the **hysteresis**. This behavior is common in transformers and electric motors, where energy is lost due to this lag in the magnetization process.

In summary, hysteresis in electricity happens when a material’s response (like its magnetization) depends not only on the current value of the applied field but also on the history of the field.