Conserved current

Imagine you have a toy car that moves around a race track. When the car moves, it pushes the air particles around it. These air particles create a force that helps the car move forward. This force is called a current.

Now, let's say you have another toy car on a different track. This car also creates a current when it moves, but it doesn't interact with the first car. The two currents are separate.

But what if the two tracks were connected? When the first car moves and creates a current, that current travels through the connected tracks and affects the second car. The second car now also has a current, but it is not independent - it is connected to the first car's current.

This idea of connected currents is similar to what happens in physics. When something moves (like an electron), it creates a current. But in some cases, this current is connected to another current (like the current created by a different electron). When this happens, the two currents are not independent - they are said to be "conserved."

Conservation of current is an important concept in physics because it helps us understand how particles interact with each other. Just like the connect toy car tracks created a new, combined current, conserved currents can create new interactions between particles that we can observe and study.