Question

a)Write the relation between resistance and electrical resistivity of
the material of a conductor in the shape of a cylinder of length
and area of cross-section 'A'. Hence derive the S.I. unit of electrical
resistivity.
b)Resistance of a metal wire of length 5 m is 100 9. If the area of
cross-section of the wire is 3 x 10"m, calculate the resistivity of
the metal.​

Answer 1

Answer:

Explanation:

Resistance is a property of conductor due to which it resists the flow of electric current through it. Component that is used to resist the flow of electric current in a circuit is called resistor.

In practical applications, resistors are used to increase or decrease the electric current.

Variable Resistance: The component of an electric circuit which is used to regulate the current; without changing the voltage from the source; is called variable resistance.

Rheostat: This is a device which is used in a circuit to provide variable resistance.