Std 6 th Science- 14. Light and the Formation of Shadows

Question 1:

Choose an appropriate word and fill in the blanks.

(a) A ........... is a natural source of light.

(b) A ......... is an artificial source of light.

(c) When light passes through a prism, it gets separated into ....... colours.

(d) The image obtained in the pinhole camera is ......... .

(e) A shadow is formed when an ........... object comes in the way of light.

(f) When a ........... object comes in the way of light, light passes ......... it.

(options : seven, star, through, transparent, opaque, colors, shape, erect, inverted, luminous, candle)

Answer 1:

(a) A star is a natural source of light.

(b) A candle is an artificial source of light.

(c) When light passes through a prism, it gets separated into seven colours.

(d) The image obtained in the pinhole camera is inverted.

(e) A shadow is formed when an opaque object comes in the way of light.

(f) When a transparent object comes in the way of light, light passes through it.

Question 2:

Write whether of the following objects are luminous or non-luminous.

Object	Luminous/Non-luminous
A book
A burning candle
A wax cloth
A pencil
A pen
A light bulb
A tyre
A torch

Answer 2:

Object	Luminous/Non-luminous
A book	Non-luminous
A burning candle	Luminous
A wax cloth	Non-luminous
A pencil	Non-luminous
A pen	Non-luminous
A light bulb	Luminous
A tyre	Non-luminous
A torch	Luminous

Question 3:

Match the following.

Group A	Group B
(a) Mirror	(1) Non-luminous
(b) Firefly	(2) Inverted image
(c) Pinhole camera	(3) Reflection
(d) Moon	(4) Luminous

Answer 3:

Group A	Group B
(a) Mirror	(3) Reflection
(b) Firefly	(4) Luminous
(c) Pinhole camera	(2) Inverted image
(d) Moon	(1) Non-luminous

Question 4:

Write the answers to the following.

(a) What things are necessary for the formation of a shadow ?

(b) When can an object be seen?

(c) What is a shadow?

Answer 4:

(a) The things necessary for the formation of a shadow are:

• A source of light
• An opaque object whose shadow has to be formed
• A screen on which shadow is to be formed

(b) An object is seen when the light rays reflected from its surface reaches our eyes.

(c) Shadow is a dark patch obtained on a screen where the light from a light source is blocked by an opaque object.