One likes to sit under sunshine in the winter season,because

The following graph shows the correct variation in the intensity of heat radiations emitted by a black body with respect to frequency at different fixed temperatures. Identify the correct graph.

Three very large plates of the same area are kept parallel and close to each other. They are considered as ideal black surfaces and have very high thermal conductivity. The first and third plates are maintained at temperatures $2\ T$ and $3\ T$ respectively. The temperature of the middle (i.e.,second) plate under steady-state condition is

Regarding black body radiation,which one of the following is the $WRONG$ statement?

What are heat rays?

The spectrum of black body radiation is a ...... .