Question

Write two different activities to show that black bodies are good absorbers of heat and good radiators of heat.

Answer 1

Black is the best emitter because if something is black it means it's strongly coupled to the electromagnetic field.

Ever notice that thermal blankets are shiny? Shiny materials are weakly coupled to the electromagnetic field. They're shiny precisely because they reflect incoming radiation instead of absorbing it. Since bad absorbers are bad emitters, this also means that when you wrap yourself in a shiny blanket you will radiate away your body heat more slowly, keeping you warmer in a cold environment. Of course, wearing a shiny blanket would also prevent you from warming up in the sun light. The way to think about it is that the shiny thing isolates you from the surroundings: it prevents you from getting warmed by incoming radiation, and it keeps you from getting cold from outgoing radiation.
This is also why thermos bottles are shiny.

Answer 2

Answer:

show that black bodies are good absorbers and good conductors of heat