Question

The electrical resistance of a conductor depends upon.
(A) Size of conductor
(B) Temperature of conductor
(C) Geometry of conductor
(D) All of these

Answer 1

Hint: - Resistance of a conductor is the property by which it opposes the flow of charge through it. It is equal to the ratio of the potential difference applied through the conductor to the current flowing through it. As it is a physical quantity of a conductor it must depend upon the physical along with structural characteristics of the conductor.

Complete step-by-step solution:
The materials which conduct electric current or any form of energy properly well are called conductors. For example all metals.
The resistance of a conductor is said to be one ohm if a current of one ampere flows through it on applying a potential of one volt across its ends.
Factors on which the resistance of a conductor of the shape of the wire depends:
The first factor is that the resistance of the conductor is directly proportional to its length.
$R\alpha l$........... $\left( 1 \right)$
The second factor is that the resistance of a straight conductor is inversely proportional to its area of cross-section.
$R\alpha \dfrac{1}{A}$ ........... $\left( 2 \right)$
$A$ = Area of the cross-section
$l$ = length
The third factor is that the resistance of a conductor also depends on the nature of the material it is made up of. For example, the resistance of nichrome wire is $60$ times that of a copper wire of equal length and area of cross-section.
Combining all the above expressions, we get
$R = \rho \dfrac{l}{A}$
where $\rho $ is the constant of proportionality known as resistivity or specific resistance of the material of the conductor.
Additionally, it also depends upon physical conditions like temperature and pressure but is independent of its shape and size.

As a result, the correct answer is (D) All of these.

Note: It should be noted that the resistance of a material may change with change in the length and cross-sectional area of the conductor but the resistivity of a conductor is constant and does not change with change in dimensions of the conductor.