A piece of iron is gradually heated in a laboratory from room temperature to a white glow
PHYSICS · Multi-part · CBSE · Physics · Thermal Properties of Matter · Thermal Properties of Matter
Problem
A piece of iron is gradually heated in a laboratory from room temperature to a white glow.
Answer the following questions related to this observation.
(i) State the physical law that relates the wavelength at which an ideal blackbody emits maximum radiation to its absolute temperature.
(ii) Using the law stated in part (i), explain qualitatively why the colour of the iron changes successively from dull red to orange, yellow, and finally nearly white as its temperature rises.
(iii) Describe how astronomers use the same law to estimate the surface temperatures of stars from the colour observed through a telescope.