NCERT Solutions for Class 6 Science - Light Shadow and Reflections

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

Ans: The given boxes can be rearranged to form ‘Opaque Objects Make Shadows’ as shown below

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, moon.
Ans: 

Opaque: A piece of rock, a sheet of aluminium, a mirror, a wooden board, a CD, 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, kerosene stove, sun, firefly, moon.
Transparent: Air, water, a sheet of plane glass.
Translucent: A sheet of polythene, smoke, fog, a sheet of cellophane, a wire mesh.

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

Getting circular shadow with a cylinder 

Getting a rectangular shadow with a cylinderQ4. 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?
Ans: No, in a dark room, a mirror reflection of the image will not be shown as the light will not fall on the mirror to reflect the image due to darkness.