Question

Classify the objects or materials given below as opaque, transparent or translucent, luminous or non-luminous:

Air, water, piece of rock, sheet of aluminium, mirror, wooden board, sheet of polythene, CD, smoke, sheet of plane glass, fog, piece of red hot iron, umbrella, lighted florescent tube, wall, sheet of carbon paper, flame of a gas burner, sheet of cardboard, lighted torch, sheet of cellophane, wire mesh, kerosene stove, sun, firefly, moon.

Answer 1

Object	Object is Transparent/Translucent/Opaque	Object is Luminous/Non-luminous
Air	Transparent	Non-luminous
Water	Transparent	Non-luminous
Piece of rock	Opaque	Non-luminous
Sheet of aluminium	Opaque	Non-luminous
Mirror	Opaque	Non-luminous
Wooden board	Opaque	Non-luminous
Sheet of polythene	Translucent	Non-luminous
CD	Translucent	Non-luminous
Smoke	Translucent	Non-luminous
Sheet of plane glass	Transparent	Non-luminous
Fog	Translucent	Non-luminous
Piece of red hot iron	Opaque	Luminous
Umbrella	Opaque	Non-luminous
Lighted fluorescent tube	Opaque	Luminous
Wall	Opaque	Non-luminous
Sheet of carbon paper	Opaque	Non-luminous
Flame of a gas burner	Translucent	Luminous
Sheet of cardboard	Opaque	Non-luminous
Lighted torch	Opaque	Luminous
Sheet of cellophane	Translucent	Non-luminous
Wire mesh	Translucent	Non-luminous
Kerosene stove	Opaque	Luminous
Sun	Opaque	Luminous
Firefly	Opaque	Luminous
Moon	Opaque	Non-luminous