Textbook: Light and the Formation of Shadows | General Science Class 6 (Maharashtra Board) PDF Download

 Page 1


97
1.  Can we see anything in total darkness ?
2.  What helps us to see the objects around us ?
3.  What does the light in each one of the pictures 
originate from ?
The objects or materials which emit light, 
meaning those which themselves are a source of 
light, are called luminous objects or materials. 
The intensity of light is determined by the extent to 
which the objects emit light. For example, the light 
emitted by an electric torch is more intense than 
that obtained from a candle.
Take three cardboards. Make a small hole in the centre of each cardboard using a thick 
needle. Arrange the cardboards in such a way that the three holes are in the same line, as 
shown in figure 14.3 on page 98. Stand a burning candle on one side of the cardboards 
and look at the flame of the candle from the other side.
14.1 : Sources of light
14.2 Light entering 
through a window
The propagation of light
You may have seen in the afternoon, rays of 
light entering through a slit in a door or a small hole 
in the roof. As these rays of light from the slit or the 
hole move towards the floor, the dust particles in 
their way are seen clearly. Due to these particles, 
the path of the light becomes visible and we can 
see that their path is along straight lines.
The objects or materials that are not sources of 
light themselves, are called non-luminous objects 
or materials. 
Some man-made objects or materials also emit 
light. These are called artificial sources of light.
The Sun is the main natural source of light. 
Other stars seen in the night sky, fireflies, some 
anglerfish as well as honey mushroom are natural 
sources of light.
Make a list of some luminous 
objects and substances and 
classify them into natural and 
artificial sources of light.
Light and the Formation of Shadows 14.
Can you tell ?    
Let’s try this.
Use your brain power !
Page 2


97
1.  Can we see anything in total darkness ?
2.  What helps us to see the objects around us ?
3.  What does the light in each one of the pictures 
originate from ?
The objects or materials which emit light, 
meaning those which themselves are a source of 
light, are called luminous objects or materials. 
The intensity of light is determined by the extent to 
which the objects emit light. For example, the light 
emitted by an electric torch is more intense than 
that obtained from a candle.
Take three cardboards. Make a small hole in the centre of each cardboard using a thick 
needle. Arrange the cardboards in such a way that the three holes are in the same line, as 
shown in figure 14.3 on page 98. Stand a burning candle on one side of the cardboards 
and look at the flame of the candle from the other side.
14.1 : Sources of light
14.2 Light entering 
through a window
The propagation of light
You may have seen in the afternoon, rays of 
light entering through a slit in a door or a small hole 
in the roof. As these rays of light from the slit or the 
hole move towards the floor, the dust particles in 
their way are seen clearly. Due to these particles, 
the path of the light becomes visible and we can 
see that their path is along straight lines.
The objects or materials that are not sources of 
light themselves, are called non-luminous objects 
or materials. 
Some man-made objects or materials also emit 
light. These are called artificial sources of light.
The Sun is the main natural source of light. 
Other stars seen in the night sky, fireflies, some 
anglerfish as well as honey mushroom are natural 
sources of light.
Make a list of some luminous 
objects and substances and 
classify them into natural and 
artificial sources of light.
Light and the Formation of Shadows 14.
Can you tell ?    
Let’s try this.
Use your brain power !
98
Reflection of light
How do we see an object ?
The rays of light falling on an  
object from a source of light are thrown 
back from the surface of that object. This 
is called reflection of light. We see the  
object when the reflected rays reach our 
eyes.
14.3 How light travels
Step 1 
Look at the flame of the candle
Step 2 
Step 1 
14.4 : Looking at the candle
Step 2 
Object
Source of light
Do you see the flame ?
Now move any one of the cardboards.
Why do you not see the flame ?
Stars are luminous. Planets, satellites are  
non-luminous. Sunlight reflected from the surface 
of the moon reaches us. That is how we can see 
the moon. We call this light moonlight.
In which step is the 
flame of the candle seen 
clearly ? Why ?
Light travels in a straight line. This is called the linear propagation of light.
14.5 : How an object is seen
Do you know ?
Use your brain 
power !
Let’s try this.
Take a straight tube that can be bent easily. As shown in the 
figure, place a burning candle on a stand, and look at it through 
the tube. Then bend the tube and look at the candle again. 
What do you see ?
Page 3


97
1.  Can we see anything in total darkness ?
2.  What helps us to see the objects around us ?
3.  What does the light in each one of the pictures 
originate from ?
The objects or materials which emit light, 
meaning those which themselves are a source of 
light, are called luminous objects or materials. 
The intensity of light is determined by the extent to 
which the objects emit light. For example, the light 
emitted by an electric torch is more intense than 
that obtained from a candle.
Take three cardboards. Make a small hole in the centre of each cardboard using a thick 
needle. Arrange the cardboards in such a way that the three holes are in the same line, as 
shown in figure 14.3 on page 98. Stand a burning candle on one side of the cardboards 
and look at the flame of the candle from the other side.
14.1 : Sources of light
14.2 Light entering 
through a window
The propagation of light
You may have seen in the afternoon, rays of 
light entering through a slit in a door or a small hole 
in the roof. As these rays of light from the slit or the 
hole move towards the floor, the dust particles in 
their way are seen clearly. Due to these particles, 
the path of the light becomes visible and we can 
see that their path is along straight lines.
The objects or materials that are not sources of 
light themselves, are called non-luminous objects 
or materials. 
Some man-made objects or materials also emit 
light. These are called artificial sources of light.
The Sun is the main natural source of light. 
Other stars seen in the night sky, fireflies, some 
anglerfish as well as honey mushroom are natural 
sources of light.
Make a list of some luminous 
objects and substances and 
classify them into natural and 
artificial sources of light.
Light and the Formation of Shadows 14.
Can you tell ?    
Let’s try this.
Use your brain power !
98
Reflection of light
How do we see an object ?
The rays of light falling on an  
object from a source of light are thrown 
back from the surface of that object. This 
is called reflection of light. We see the  
object when the reflected rays reach our 
eyes.
14.3 How light travels
Step 1 
Look at the flame of the candle
Step 2 
Step 1 
14.4 : Looking at the candle
Step 2 
Object
Source of light
Do you see the flame ?
Now move any one of the cardboards.
Why do you not see the flame ?
Stars are luminous. Planets, satellites are  
non-luminous. Sunlight reflected from the surface 
of the moon reaches us. That is how we can see 
the moon. We call this light moonlight.
In which step is the 
flame of the candle seen 
clearly ? Why ?
Light travels in a straight line. This is called the linear propagation of light.
14.5 : How an object is seen
Do you know ?
Use your brain 
power !
Let’s try this.
Take a straight tube that can be bent easily. As shown in the 
figure, place a burning candle on a stand, and look at it through 
the tube. Then bend the tube and look at the candle again. 
What do you see ?
99
14.6 : An image
2. What is the difference between an object and 
its reflection ? What causes the difference ?
Let us see how light is reflected from the 
three surfaces shown alongside.
When you see your face in a mirror, the light reflected 
from your face falls on the mirror, and gets reflected back 
again. That is why you see the image in the mirror.
Do you see your image in a glass pane ? You do, 
although it is somewhat faint. No image will be seen at 
all on a wooden surface.
You may have seen your image formed in surfaces such 
as a new steel dish, the glossy granite cladding of a wall 
and the still water in a lake. Make a list of other similar 
surfaces. Compare the images seen in them. Make a guess 
about the property of a surface due to which an image is 
formed. Discuss this with your teachers and parents.   
Images in a plane mirror
 
Stand in front of a plane mirror and look at your image in it.
 1.  Raise your right hand. Which hand of the mirror image 
is raised ?
 2.  What change do you see in the image if you decrease or 
increase your distance from the mirror ?
 3.  Is there any difference between your height and height 
of the mirror image ?
 1.  In which objects 
do we see a reflection?
14.7 : The image in a plane mirror
l  The left and right sides of the original object appear 
to be exchanged in the mirror image.
l  The image is as far behind the mirror as the object 
is in front of it. 
l  The size of the image is the same as that of the 
object.
1. How will you light up a dark room using 
reflected light?
2. Try to start the TV by operating the remote 
control from behind it.
Can you tell ?    
Let’s try this.
Use your brain power !
Page 4


97
1.  Can we see anything in total darkness ?
2.  What helps us to see the objects around us ?
3.  What does the light in each one of the pictures 
originate from ?
The objects or materials which emit light, 
meaning those which themselves are a source of 
light, are called luminous objects or materials. 
The intensity of light is determined by the extent to 
which the objects emit light. For example, the light 
emitted by an electric torch is more intense than 
that obtained from a candle.
Take three cardboards. Make a small hole in the centre of each cardboard using a thick 
needle. Arrange the cardboards in such a way that the three holes are in the same line, as 
shown in figure 14.3 on page 98. Stand a burning candle on one side of the cardboards 
and look at the flame of the candle from the other side.
14.1 : Sources of light
14.2 Light entering 
through a window
The propagation of light
You may have seen in the afternoon, rays of 
light entering through a slit in a door or a small hole 
in the roof. As these rays of light from the slit or the 
hole move towards the floor, the dust particles in 
their way are seen clearly. Due to these particles, 
the path of the light becomes visible and we can 
see that their path is along straight lines.
The objects or materials that are not sources of 
light themselves, are called non-luminous objects 
or materials. 
Some man-made objects or materials also emit 
light. These are called artificial sources of light.
The Sun is the main natural source of light. 
Other stars seen in the night sky, fireflies, some 
anglerfish as well as honey mushroom are natural 
sources of light.
Make a list of some luminous 
objects and substances and 
classify them into natural and 
artificial sources of light.
Light and the Formation of Shadows 14.
Can you tell ?    
Let’s try this.
Use your brain power !
98
Reflection of light
How do we see an object ?
The rays of light falling on an  
object from a source of light are thrown 
back from the surface of that object. This 
is called reflection of light. We see the  
object when the reflected rays reach our 
eyes.
14.3 How light travels
Step 1 
Look at the flame of the candle
Step 2 
Step 1 
14.4 : Looking at the candle
Step 2 
Object
Source of light
Do you see the flame ?
Now move any one of the cardboards.
Why do you not see the flame ?
Stars are luminous. Planets, satellites are  
non-luminous. Sunlight reflected from the surface 
of the moon reaches us. That is how we can see 
the moon. We call this light moonlight.
In which step is the 
flame of the candle seen 
clearly ? Why ?
Light travels in a straight line. This is called the linear propagation of light.
14.5 : How an object is seen
Do you know ?
Use your brain 
power !
Let’s try this.
Take a straight tube that can be bent easily. As shown in the 
figure, place a burning candle on a stand, and look at it through 
the tube. Then bend the tube and look at the candle again. 
What do you see ?
99
14.6 : An image
2. What is the difference between an object and 
its reflection ? What causes the difference ?
Let us see how light is reflected from the 
three surfaces shown alongside.
When you see your face in a mirror, the light reflected 
from your face falls on the mirror, and gets reflected back 
again. That is why you see the image in the mirror.
Do you see your image in a glass pane ? You do, 
although it is somewhat faint. No image will be seen at 
all on a wooden surface.
You may have seen your image formed in surfaces such 
as a new steel dish, the glossy granite cladding of a wall 
and the still water in a lake. Make a list of other similar 
surfaces. Compare the images seen in them. Make a guess 
about the property of a surface due to which an image is 
formed. Discuss this with your teachers and parents.   
Images in a plane mirror
 
Stand in front of a plane mirror and look at your image in it.
 1.  Raise your right hand. Which hand of the mirror image 
is raised ?
 2.  What change do you see in the image if you decrease or 
increase your distance from the mirror ?
 3.  Is there any difference between your height and height 
of the mirror image ?
 1.  In which objects 
do we see a reflection?
14.7 : The image in a plane mirror
l  The left and right sides of the original object appear 
to be exchanged in the mirror image.
l  The image is as far behind the mirror as the object 
is in front of it. 
l  The size of the image is the same as that of the 
object.
1. How will you light up a dark room using 
reflected light?
2. Try to start the TV by operating the remote 
control from behind it.
Can you tell ?    
Let’s try this.
Use your brain power !
100
A pinhole camera
Take an empty cylindrical box. Remove its cap on one side and 
paste a thin white paper in its place. Make a small hole at the centre 
14.8 : Pinhole camera
Why is the image 
on the diaphragm of 
the pinhole camera 
inverted ?
14.9 : Window
Depending on the nature of the 
window pane, we may or may not see 
the objects on the other side through it.
Identify the transparent, opaque 
and translucent objects from among the 
following : piece of a glass, wax paper, 
tinted glass, oil paper, white plastic, a 
tea kettle, a notebook, cloth, water, a 
wooden cupboard, sheet of a notebook.
l The material through which light passes is said to be transparent.
l The material through which light does not pass is said to be opaque.
l The material through which light passes partially is said to be translucent.
1.  What difference do you notice on looking through the 
windows in the picture ? What causes the difference ?
14.10 :  Formation of a shadow
Formation of shadow
Thin 
paper
Cap
Candle
Inverted
image
Hole
Take an electric torch. Flash its light 
on a wall. Now make your friend stand 
in between the torch and the wall.  
What  happens ?
Try this.
Can you tell ?    
Let’s try this.
Use your 
brain power!
of the other cap. Light a candle and hold the box in such a way that the flame of the candle 
is in front of the hole. Now you will see an upside down or inverted image of the flame on 
the thin paper at the other end.
2.  The picture shows transparent, opaque, translucent  window panes. Spot them.
Page 5


97
1.  Can we see anything in total darkness ?
2.  What helps us to see the objects around us ?
3.  What does the light in each one of the pictures 
originate from ?
The objects or materials which emit light, 
meaning those which themselves are a source of 
light, are called luminous objects or materials. 
The intensity of light is determined by the extent to 
which the objects emit light. For example, the light 
emitted by an electric torch is more intense than 
that obtained from a candle.
Take three cardboards. Make a small hole in the centre of each cardboard using a thick 
needle. Arrange the cardboards in such a way that the three holes are in the same line, as 
shown in figure 14.3 on page 98. Stand a burning candle on one side of the cardboards 
and look at the flame of the candle from the other side.
14.1 : Sources of light
14.2 Light entering 
through a window
The propagation of light
You may have seen in the afternoon, rays of 
light entering through a slit in a door or a small hole 
in the roof. As these rays of light from the slit or the 
hole move towards the floor, the dust particles in 
their way are seen clearly. Due to these particles, 
the path of the light becomes visible and we can 
see that their path is along straight lines.
The objects or materials that are not sources of 
light themselves, are called non-luminous objects 
or materials. 
Some man-made objects or materials also emit 
light. These are called artificial sources of light.
The Sun is the main natural source of light. 
Other stars seen in the night sky, fireflies, some 
anglerfish as well as honey mushroom are natural 
sources of light.
Make a list of some luminous 
objects and substances and 
classify them into natural and 
artificial sources of light.
Light and the Formation of Shadows 14.
Can you tell ?    
Let’s try this.
Use your brain power !
98
Reflection of light
How do we see an object ?
The rays of light falling on an  
object from a source of light are thrown 
back from the surface of that object. This 
is called reflection of light. We see the  
object when the reflected rays reach our 
eyes.
14.3 How light travels
Step 1 
Look at the flame of the candle
Step 2 
Step 1 
14.4 : Looking at the candle
Step 2 
Object
Source of light
Do you see the flame ?
Now move any one of the cardboards.
Why do you not see the flame ?
Stars are luminous. Planets, satellites are  
non-luminous. Sunlight reflected from the surface 
of the moon reaches us. That is how we can see 
the moon. We call this light moonlight.
In which step is the 
flame of the candle seen 
clearly ? Why ?
Light travels in a straight line. This is called the linear propagation of light.
14.5 : How an object is seen
Do you know ?
Use your brain 
power !
Let’s try this.
Take a straight tube that can be bent easily. As shown in the 
figure, place a burning candle on a stand, and look at it through 
the tube. Then bend the tube and look at the candle again. 
What do you see ?
99
14.6 : An image
2. What is the difference between an object and 
its reflection ? What causes the difference ?
Let us see how light is reflected from the 
three surfaces shown alongside.
When you see your face in a mirror, the light reflected 
from your face falls on the mirror, and gets reflected back 
again. That is why you see the image in the mirror.
Do you see your image in a glass pane ? You do, 
although it is somewhat faint. No image will be seen at 
all on a wooden surface.
You may have seen your image formed in surfaces such 
as a new steel dish, the glossy granite cladding of a wall 
and the still water in a lake. Make a list of other similar 
surfaces. Compare the images seen in them. Make a guess 
about the property of a surface due to which an image is 
formed. Discuss this with your teachers and parents.   
Images in a plane mirror
 
Stand in front of a plane mirror and look at your image in it.
 1.  Raise your right hand. Which hand of the mirror image 
is raised ?
 2.  What change do you see in the image if you decrease or 
increase your distance from the mirror ?
 3.  Is there any difference between your height and height 
of the mirror image ?
 1.  In which objects 
do we see a reflection?
14.7 : The image in a plane mirror
l  The left and right sides of the original object appear 
to be exchanged in the mirror image.
l  The image is as far behind the mirror as the object 
is in front of it. 
l  The size of the image is the same as that of the 
object.
1. How will you light up a dark room using 
reflected light?
2. Try to start the TV by operating the remote 
control from behind it.
Can you tell ?    
Let’s try this.
Use your brain power !
100
A pinhole camera
Take an empty cylindrical box. Remove its cap on one side and 
paste a thin white paper in its place. Make a small hole at the centre 
14.8 : Pinhole camera
Why is the image 
on the diaphragm of 
the pinhole camera 
inverted ?
14.9 : Window
Depending on the nature of the 
window pane, we may or may not see 
the objects on the other side through it.
Identify the transparent, opaque 
and translucent objects from among the 
following : piece of a glass, wax paper, 
tinted glass, oil paper, white plastic, a 
tea kettle, a notebook, cloth, water, a 
wooden cupboard, sheet of a notebook.
l The material through which light passes is said to be transparent.
l The material through which light does not pass is said to be opaque.
l The material through which light passes partially is said to be translucent.
1.  What difference do you notice on looking through the 
windows in the picture ? What causes the difference ?
14.10 :  Formation of a shadow
Formation of shadow
Thin 
paper
Cap
Candle
Inverted
image
Hole
Take an electric torch. Flash its light 
on a wall. Now make your friend stand 
in between the torch and the wall.  
What  happens ?
Try this.
Can you tell ?    
Let’s try this.
Use your 
brain power!
of the other cap. Light a candle and hold the box in such a way that the flame of the candle 
is in front of the hole. Now you will see an upside down or inverted image of the flame on 
the thin paper at the other end.
2.  The picture shows transparent, opaque, translucent  window panes. Spot them.
101
Compare this.
Compare the objects in your environment with the shadows they form.
1.  Send the friend closer to the wall.
2.  Ask the friend to come towards you.
3.  Next, you move further away from him  
and towards him again.
4.  Hold the torch high and then low. 
5.  Go toward the left and then to the right 
of the friend.
Ask your friend to stand at a certain distance from you in a 
big room and obtain the shadow of your friend on the wall with the 
help of a torch. Now carry out the following actions. Observe and 
make a note of the changes taking place in the shadow.
The shadow of an object is formed only when light does not pass through the 
object. The kind of shadow it forms depends upon the relative distances between the 
source of light, the object and the surface or the screen on which the shadow is formed.
The shadow of an object formed due to sunlight is long in the mornings and 
evenings and short in the afternoon. We can easily note these changes if we observe 
the trees along the roadside. This change in the shadow depends on the source of light, 
the object and also on the surface on which the shadow is formed.
If an opaque object comes in the way of a light source, light does not pass through it. 
As a result, the light does not reach a wall or any other surface on the other side of the 
object. That part remains dark. This dark part is called the ‘shadow of the object’.
Try this.