CBSE Class 10 Answered

A material looks black because it absorbs most of the light in the visible spectrum (i.e. the colours of the rainbow from red to violet) and does not do not emit or reflect light in any part of the visible spectrum . A green coloured object appears green because the green part of the spectrum gets rebounded off the object into our eyes.

So black absorbs much more energy than other colours because every other color reflects back at least some of the light; but black colour is not a good reflector.