Question

The thermal conductivity of a rod depends on:
A. length
B. mass
C. area of cross-section
D. material of rod

Answer 1

Hint: In this question, we can find the effects of any physical quantity by explaining the formula of the coefficient of thermal conductivity. Some of the physical quantities are the characteristics of the material which may affect the coefficient of thermal conductivity.

Complete step-by-step solution:
Thermal conductivity is a property related to the property of material.
If The length of a rod is \[L\] and the surface area of material (cross-section of the rod) is \[A\] . Let \[{T_1}\] is the temperature of the first end of the rod and the \[{T_2}\] is the temperature of the other end of the rod. Then the temperature difference will become \[({T_2} - {T_1})\] . If \[Q\] is the quantity of heat flow then the thermal conductivity of the rod \[k\] is given as-
$k = \dfrac{{QL}}{{A({T_2} - {T_1})}}$
So, the coefficient of thermal conductivity of rod depends on the following as per the formula-
->Change in temperature
->Length of the rod.
->Material of the rod.
->Cross-section of the rod.
Hence, the thermal conductivity of a rod depends on length, area of cross-section and material of rod.Therefore, option A, option C and option D are correct.

Additional Information: - Thermal property is the property which is also known as transport property. It provides the rate at which the energy is transferred. It depends on the state of matter (physical structure of matter either atomic or molecular).

Note:- In this question, we have to remember the formula of the coefficient of conductivity to find the effect of length of the rod, mass of rod, area of cross section of the rod and material of the rod.