Chapter 11: Light, Shadows and Reflections

Science

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Chapter 11: Light, Shadows and Reflections

Class VI

NCERT solutions

Question 1

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

Answer 1

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 aluminum, 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 2

Opaque: A piece of rock, a sheet of aluminum, 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.

Translucent: A sheet of polythene, smoke, a sheet of plane glass, 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 aluminum, 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.

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 3

A cylinder object can cast shadows in two ways. When the top circular view faces the shining object, a circular shape shadow is formed. When its curved side faces the shining object, it casts a rectangular shadow.

Question 4

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 4

No, to see the reflection, source of light is required. We can see only in the presence of light.