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A blackbody absorbs all radiations whereas a white body reflects most of them. This is shown by a simple experiment.
Procedure: Take two containers of same size (you can use cold drink cans for this). Paint one container with white color and other with black color. Fill containers with water and keep the containers in the sun light. After 15 minutes or so, check the temperature of each container. You will find the container with black walls is at a higher temperature.
Discussion: A blackbody absorbs more radiation energy than a white body. A white body reflects radiations of all colors of light whereas a black body absorbs radiations of all colors.
All black bodies emit radiation. The energy radiated by a body depends on its temperature, surface area and nature of surface.
Black painted bodies radiate more than that radiated by reflective bodies if the temperature and area are the same. This experiment makes a qualitative comparison of the heat radiated by a black and a shining body.
You need an electric iron, two thermometers, stand. The electric iron given is painted black at half the surface (left half if you look the surface from front) and is left in its original shining state for the other half. Place it in its common position.
As this is the same iron, the temperature of the iron surface is almost the same at any given time. Remember, heating of the iron takes place due to the heating element inside which carries the current and not due to any radiation absorbed by the surface.
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