if a black body absorbs heat then why does the cooling glass looks black?

Answer 1

Dark surfaces do absorb heat faster than light surfaces but they also emit heat faster.

Remember the US spy plane, the SR-71 (blackbird)?
It was painted a high-emissivity blue to keep the skin temperature at acceptable levels.

Answer 2

A black body emits heat in addition to absorbing it.

If the body is cooler than the surroundings, there is a net heating effect.

If the body is warmer than its surroundings (as in your cooling glass example), then there is a net cooling effect.

Answer 3

A. The 'stone' of a mood ring can be a hollow quartz or glass shell containing thermotropic liquid crystals. present day mood rings is frequently made from a flat strip of liquid crystals with a preserving coating. The crystals respond to ameliorations in temperature by skill of twisting. The twisting ameliorations their molecular structure, which alters the wavelengths of sunshine that are absorbed or meditated. 'Wavelengths of sunshine' is yet differently of preserving 'colour', so even as the temperature of the liquid crystals ameliorations, so does their colour.

Answer 4

To Absorb heat from what you are cooling...

Answer 5

It does absorb. In this case it absorbs most light and allow only little to see.

Answer 6

Black as a reflected “color” is all colors combined, while actual black refracted is the absence of light. I would guess that your cooling glass is polarized.