NCERT Solutions for Class-6 Science Chapter-11 Light, Shadows and Reflections

NCERT TEXTBOOK EXERCISES

Question 1. Rearrange the boxes given below to make a sentence that helps us understand opaque objects.

Answer:

Question 2. 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.
Answer:
1. Transparent objects: Air, water, a sheet of plane glass.
2. Translucent objects: A sheet of polythene, smoke, fog, a sheet of cellophane, a wire mesh.
3. Opaque objects: A piece of rock, a sheet of aluminium, a mirror, a wooden board, a CD, an umbrella, a wall, a sheet of carbon paper, a sheet of cardboard.
4. Luminous objects: A piece of red hot iron, a lighted fluorescent tube, the flame of a gas burner, a lighted torch, kerosene stove, sun, firefly.
5. Non-luminous objects: Include all,
(a) transparent objects,
(b) translucent objects and
(c) opaque objects and moon.

Question 3. 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, there are many things which give a circular shadow if held in one way and a rectangular shadow if held in another way. For example, a cylinder, a circular disc, etc.

Question 4. In a completely dark room, if you hold up a mirror in front of you, you see a reflection of yourself in the mirror?
Answer: No, we will not see the image because there is no light.