# Q & A: How do Variable Resistors work?

Q:
We are learning with circuits in physics, and my teacher didnt explain how a variable resistor works, he just told us what it did. Does it have something to do with the amount of coils?
- Jason (age 12)
Orange County usa
A:
Hello Jason,

A variable resistor is very important. It allows you to build a circuit with some degree of control. For example, a volume knob can be a variable resistor. It can act as a control on the amount of current flowing. Here is a picture of a variable resistor from a dimmer switch.

A variable resistor works by adjusting the path that current has to flow. Inside the resistor is a strip of metal or conducting ceramic which is connected to one part of the circuit. The dial you turn will move another piece of wire inside the resistor. The end result is that the electricity will travel through a certain length of the strip depending on where you turn the knob. When the electricty goes through a longer path, it will encounter more resistance.