# Cause Of Resistance In A Conductor

The resistance of a conductor is defined as the resistance offered by the conductor for the flow of electric current through it. The SI unit of resistance is Ohm. The mathematical representation is given as:

 $$R=\frac{V}{I}$$

Where,

• R is the resistance
• V is the potential difference
• I is the current

Resistance is caused in a conductor by the free electrons. These free electrons collide with each other and with the ions and atoms that oppose their free movement. This obstruction is known as resistance.

Resistance depends on the following factors:

• Length of the conductor
• Area of cross-section
• Material of construction