Resistor: The wire that opposes (resists) the flow of current through it by virtue of its property is called resistor. This property is known as resistance. The resistance is measured in ohms.
R = ρL/A
where
R = Resistance of wire,
A = cross section area of wire,
L = length of wire, and
ρ = resistivity of wire material.
Resistor
Thus, by increasing length of wire, the resistance increases and by increasing thickness of wire, the resistance decreases.