Light, Shadows and Reflections Question Answers: NCERT Class 6 Science

The objects from which light cannot pass through, are called opaque objects. When any opaque object comes in the path of light, then a dark structure is formed called shadow.

Opaque: A piece of rock, a CD, smoke, iron, an umbrella, a wall, a sheet of aluminium.

Transparent: Air, water, sheet of plane glass.

Translucent: A sheet of polythene, fog, a sheet of cellophone.

Luminous: A lightened fluorescent tube, flame of gas burner, a lighted torch, firefly, stove, sun, moon.

Non- luminous: A mirror, piece of rock, a wire mesh, iron, a wall.

• The objects through which lights cannot pass are called as opaque objects.
• Objects from which lights can pass easily and we can see clearly through them are called transparent objects.
• The objects from which lights can pass easily but we cannot see clearly are known as translucent objects.
• The objects which emits light are called as luminous.
• The objects which does not emit light are known as non- luminous objects.

Yes, a cylindrical shape is one which gives the circular shadow from one end and a rectangular shadow from another end.

No, in a complete dark room we cannot see the reflection in the mirror because reflection is the phenomenon of light. If there is no light then reflection does not occur there and we cannot see our image in the mirror.