Question

Resistivity of a given conductor depends upon
A. temperature
B. length of conductor
C. area of cross section
D. shape of the conductor

Answer 1

In order to solve this question you have to remember all the concepts related to resistivity. Recall the relation between resistance, resistivity, length of the conductor and the area of cross section. Always remember that the resistivity is the property of the material of wire.

Complete step by step solution:
Resistance is the property of the conductor that opposes the flow of electric current and the resistivity is defined as the resistance offered by the material per unit length for unit cross-section.
The resistivity is the property of the material which depends on the nature and the composition of the material and the composition is affected by the temperature.
$R = \dfrac{{\rho l}}{A}$
Here, $R$ is the resistance of the conductor
$\rho$ is the resistivity of the conductor
$l$ is the length of the conductor
$A$ is the area of cross-section of the conductor
And the length and area of the cross-section is affected by the resistance, not the resistivity.
Hence, the resistivity depends on the temperature.

Therefore, the correct option is (A) temperature

Note: Remember that the SI unit of the resistivity is Ohm meter. Resistivity of the conductor increases linearly with the temperature. The resistivity of the inductor is high when we compare with the resistivity of the conductors. The resistivity of alloy lies between the resistivity of the conductor and the resistivity of the inductors.
The property of resistance is used in several places like fuses, sensors, heaters, etc. The SI unit of resistance is Ohms. Resistance is directly proportional to the length and inversely proportional to the area of cross-section of the conductor.