Question

An ideal black - body at room temperature is thrown into a furnace. It is observed that.

• A. Initially it is the darkest body and at later times the brightest
• B. It is the darkest body at all times
• C. It cannot be distinguished at all times
• D. Initially it is the darkest body and at later times it cannot be distinguished

Answer 1

The correct option is A Initially it is the darkest body and at later times the brightest

When the temperature of black body becomes equal to the temperature of furnace, it will radiate maximum energy, so it will be brightest. Initially it will absorb all radiations, so it will be darkest.