Question

In order that the heat flows from one part of a solid to another part, what is required?
A. Uniform density
B. Temperature gradient
C. Density gradient
D. Uniform temperature

Answer 1

Hint: In order to solve this problem we need to understand the rate of heat transfer. The rate of flow of heat is the amount of heat that is transferred per unit of time temperature. A temperature gradient is a change in temperature over a specified distance between two isothermal surfaces or two points in a material. Using these terms we are going to find the solution to this question.

Complete step by step solution:
A temperature gradient is always necessary for heat to flow. In anybody, heat energy always flows from the region at a higher temperature to the one at a lower temperature. Within a solid, the heat transfer is always related to its density. The denser the body, the quicker the heat transfer will be.

A presence or absence of a density gradient will still permit the flow of heat within a body but the absence of a temperature gradient prevents heat transfer through it. Hence, in option (b), the presence of a temperature gradient is a necessary condition for the transmission of heat.

Hence, option B is the correct answer.

Note: While solving this problem remember the definition of heat flow, temperature gradient and how these will impact a solid material. In order to flow heat from one part of solid material to another part of solid material, a temperature gradient is required.