Question

In steady state conduction, the temperature gradient within a solid material does not:

• A. Increase over time
• B. Decrease over time
• C. Change over time
• D. Vary spatially within the material

Hint:

In steady state conduction, temperature may vary across space but not over time. Look for keywords like “no change with time” to identify this condition.

Answer 1

The Correct Option is C

Step 1: Steady-state heat conduction refers to the condition in which the temperature distribution in a material does not change with time. This means that while heat may still be flowing through the material, the temperature at any given point remains constant over time.
Step 2: The temperature gradient (rate of temperature change with distance) remains fixed in steady state. However, it can still vary spatially within the material, depending on geometry, boundary conditions, and thermal conductivity.
Step 3: In contrast, during transient conduction (non-steady state), the temperature at points within the material changes over time until steady state is reached.
Why the other options are incorrect:

• (A) and (B) Both imply a time-dependence, which does not occur in steady state.
• (D) The gradient can vary from one point to another spatially in a solid; it is the constancy over time that defines steady state.