NCERT Solutions for Class 6 Science Chapter 11 Light Shadows And Reflections

Q1 ) Rearrange the boxes given below to make a sentence that helps us understand opaque objects.

Answer :

Q2 ) 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, the moon.

Answer :

(1) Opaque :

A piece of rock, a sheet of aluminum, a mirror, a wooden board, a CD, an umbrella, a wall, a sheet of carbon paper, a sheet of cardboard, a wire mesh, kerosene stove, sun, firefly, the moon, lighted torch.


(2) Transparent :

Air, water, a sheet of plane glass.


(3) Translucent :

A sheet of polythene, smoke, fog, flame of gas burner ,a sheet of cellophane, a wire mesh.


(4) Luminous :

A piece of red hot iron, a lighted fluorescent tube, the flame of a gas burner, a lighted torch, sun, firefly, kerosene stove.


(5) 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, an umbrella, a wall, a sheet of carbon paper, a sheet of cardboard, a sheet of cellophane, a wire mesh, moon.

Q3 ) Can you think of creating a shape that would give a circular shadow if held in one way and a rectangular shadow if held in another way?

Answer :

Yes, a cylindrical shape is the one that would give a circular shadow if held in one way and a rectangular shadow if held in another way.

Its circular ends will form a circular shadow when kept in the way of light whereas its curved sides will give a rectangular shadow.

Q4 ) In a completely dark room, if you hold up a mirror in front of you, will you see a reflection of yourself in the mirror?

Answer :

No, we will not see our reflection in the mirror in a dark room because an image is formed only when the light gets reflected by the mirror whereas, in a dark room, there is no light to cause reflection.

Hence, no image will be formed.