光遇上吸光的東西

Different componds/materials will absorb different "light", the "light" means different spectra of the whole spectrum (including that we see-white light, white light include red, orange, yellow, green, blue, violet, etc; that we call "visible light", others include "invisible light").

When one material absorbs some lights and does not absorb red light, red light is seen by us.

When one material does not absorb all the infra-red light (light with heat energy), the material can be "seen " (visualized only) by infra-red detector.

唔知呀........

黑色.....宇宙中的黑洞，它的引力大到連光也吸進去，所以也是黑色.....

大類是看不見吸光的東西，而部顏色便會吸光，如黑，而部份顏色便會反射光，如白