Determine whether the following statements are True or False:
$(a)$ "Conduction stops once a rod achieves thermal steady state."
$(b)$ $A$ surface that is a good emitter is also a good absorber.
$(c)$ $A$ perfect black body must be black in color.
$(d)$ The value of heat capacity is the same under different conditions for a given matter.

Vedclass pdf generator app on play store
Vedclass iOS app on app store
$(a)$ False. Conduction does not stop; rather, the temperature gradient becomes constant, and the rate of heat transfer remains steady.
$(b)$ True. According to Kirchhoff's law of radiation, for an arbitrary body emitting and absorbing thermal radiation in thermodynamic equilibrium, the emissivity is equal to the absorptivity.
$(c)$ False. $A$ perfect black body is defined by its ability to absorb all incident radiation, regardless of its appearance or color in the visible spectrum.
$(d)$ False. Heat capacity depends on the state of the matter (e.g., phase) and the conditions under which heat is added (e.g., constant pressure vs. constant volume).

Explore More

Similar Questions

In a closed room,heat transfer takes place by

Three discs $x, y$ and $z$ having radii $2 \ m, 2 \ m$ and $6 \ m$ respectively are coated on their outer surfaces. If the wavelengths corresponding to the maximum power radiated by them are $3 \ \mu m, 4 \ \mu m$ and $5 \ \mu m$ respectively,then which of the following is true regarding the power radiated $(P)$?

What are the modes of heat transfer due to a temperature difference?

The dimensions of $\sigma b^4$, where $\sigma$ is Stefan's constant and $b$ is Wien's constant, are:

Two rods (one semi-circular and other straight) of the same material and of the same cross-sectional area are joined as shown in the figure. The points $A$ and $B$ are maintained at different temperatures. The ratio of the heat transferred through a cross-section of the semi-circular rod to the heat transferred through a cross-section of the straight rod in a given time is

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo