Extramarks-background-image
Q:

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?

A:

In a completely dark room, there will be no light. The formation of an image depends upon the reflection of light. Therefore, no reflection of light takes place by the mirror placed in the dark room. Hence, no image will get formed by a mirror in a completely dark room.

Q:

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

A:

It would be “Opaque objects make shadows”.

Q:

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?

A:

                 

A cylinder kept in sunlight can form a circular shadow or a rectangular shadow. It can be obtained depending on its orientation related to the Sun. The cylinder forms a circular shadow when its top faces the Sun. When the side of the cylinder faces the Sun, then it forms rectangular shadow.

Q:

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.

A:

Object

Transparent
/Translucent
/Opaque

Luminous/Non-luminous

Air

Transparent

Non-luminous

Water

Transparent

Non-luminous

Piece of rock

Opaque

Non-luminous

Sheet of aluminum

Opaque

Non-luminous

Mirror

Opaque

Non-luminous

Wooden Board

Opaque

Non-luminous

Sheet of polythene

Translucent

Non-luminous

CD

Translucent

Non-luminous

Smoke

Translucent

Non-luminous

Sheet of plane glass

Translucent

Non-luminous

Fog

Translucent

Non-luminous

Piece of red hot iron

Opaque

Luminous

Umbrella

Opaque

Non-luminous

Lighted fluorescent tube

Opaque

Luminous

Wall

Opaque

Non-luminous

Sheet of carbon paper

Opaque

Non-luminous

Flame of a gas burner

Translucent

Luminous

Sheet of cardboard

Opaque

Non-luminous

Lighted torch

Opaque

Luminous

Sheet of cell phone

Translucent

Non-luminous

Wire mess

Translucent

Non-luminous

Kerosene stove

Opaque

Luminous

Sun

Opaque

Luminous

Firefly

Opaque

Luminous

Moon

Opaque

Non-luminous
Download App

Download Extramarks – The Learning App

Take your CBSE board preparation to another level with AI based and rich media animation on Extramarks - The Learning App.

Features of Learning App

  • Learn with studybot “Alex”
  • Personalized Learning journey
  • Unlimited doubt Solving
  • Quiz, challenge friends
  • Leaderboard Ranking
  • Academic Guru

Download App Download App