Resistance is the property of a conductor by which it opposes the flow of current through it.
It is determined by the relationship between the applied voltage and the electric current passing through it.
Resistance of a wire:
The resistance of a wire is inversely correlated with its cross-sectional area and directly correlated with its length. Resistance is also affected by the material of the conductor.
The fundamental behavior of electric circuits is described by Ohm's law. Voltage, resistance, and current are all directly correlated.
According to Ohm's law, resistance is a constant that is unaffected by current or voltage.
The resistance of a wire can be calculated if the length of the wire, the cross-sectional area of the wire, and the resistivity of the material are known as follows:
Where is the resistance, is the resistivity of the wire, is the length of the wire and is the area of the cross-section of the wire.
The length of the wire – Longer the wire, the greater its resistance
The cross-sectional area – the greater the area, the lesser its resistance
The resistivity of the material – the greater the resistivity, the greater its resistance.
If the voltage and current in a circuit are known, then resistance can be calculated using Ohm’s Law as follows: