Question

A black surface emits ________ heat energy than a polished or white surface even when both are at the same temperature.
A. More
B. Less
C. Same
D. None

Answer 1

Hint: In this question we should understand the black body radiation concept and what is the process involved in that.

Complete step by step answer:
Black body is the best emitter because if something is black, it means it's strongly coupled to the electromagnetic field. Practically the bodies are the good absorption of heat and similarly they are good emitters because here action and reaction processes take place hence absorption is action and the reaction is the process of emitting. And also by Kirchhoff’s law of radiation, make it evident that a black body is not only a perfect absorbed but also a perfect emitter of heat.

The material which is made up of black, its surfaces and dull surfaces produces larger heat energy compared to the light colored surfaces, polished surfaces or white colored material even when they maintain at the similar temperature.

Hence the correct option is A.

Additional information:Commonly the Black-body radiation is the thermal or thermos electromagnetic radiation within a body and its surrounded by the body in the equilibrium state of thermodynamics with respect to its environment, emitted by black surface or black body. It consists of a specific electromagnetic spectrum of certain wavelengths which is inversely proportional to the intensity that depends on the bodies’ temperature, which can be calculated.

Note:A black body or blackbody is an idealized physical body that absorbs all incident electromagnetic radiation. The name black body is given because it absorbs radiation in all frequencies, not because it only absorbs a black body can emit black-body radiation.