Question

What happens to the a) resistance and b) resistivity of a conductor if its
(i) area of cross section is doubled (ii) length is reduced to half.​

Answer 1

Answer:

The resistance of a conductor is inversely proportional to its area of cross section. A dummy approach: The concept of current flow in a conductor is analogous to liquid flow in a pipe. As the amount of current flowing at constant voltage increases with increase in cross sectional area, resistance decreases.

The larger the cross sectional area, the lower the resistance since the electrons have a larger area to flow through. This will continue to apply no matter how thick the wire is. The electron flow will adjust itself to whatever the wire thickness is. Electricity is nothing but the flow of electrons through a material.

The SI unit of electrical resistance is the ohm (Ω), while electrical conductance is measured in siemens (S). An object of uniform cross section has a resistance proportional to its resistivity and length and inversely proportional to its cross-sectional area.

Explanation: