Classify the objects or materials given below as opaque, transparent or
translucent and luminous or non-luminous:
Air, water, a piece of rock, a sheet of aluminium, a mirror, a wooden board, a
sheet of polythene, a CD, smoke, a sheet of plane glass, fog, a piece of red hot
iron, an umbrella, a lighted fluorescent tube, a wall, a sheet of carbon paper,
the flame of a gas burner, a sheet of cardboard, a lighted torch, a sheet of
cellophane, a wire mesh, kerosene stove, sun, firefly, moon,
opaque-a piece of rock, a aluminum sheet, a mirror,a wooden bord, cd,a peice of red hot iron,an umbrella,a wall,a sheet of carbon paper, a sheet of cardboard,a lighted torch,
translucent : air, water,a sheet of
polythene,smoke,plane glass, wire mesh
luminous: cd, a red hot iron, a lighted fluoro
tube, a lighted torch, flame
firefly,sun, moon
non luminous: the ones that dont produce light