RBSE Class 6 Science Important Questions Chapter 11 Light, Shadows and Reflections

Rajasthan Board  RBSE Class 6 Science Important Questions Chapter 11 Light, Shadows and Reflections Important Questions and Answers.

RBSE Class 6 Science Chapter 11 Important Questions Light, Shadows and Reflections

Multiple Choice Questions

Question 1. 
The objects that do not allow light to pass through them are:
(a) transparent 
(b) opaque 
(c) translucent 
(d) all of these
Answer:
(b) opaque 

 

Question 2. 
Light travels in:
(a) zig-zag manner 
(b) circular
(c) straight line 
(d) random motion
Answer:
(c) straight line 

Question 3. 
A is a device which can form the image of sun.
(a) glass prism
(b) wood
(c) long straight pipe
(d) pinhole camera
Answer:
(d) pinhole camera

Question 4. 
The image formed in the pinhole camera are:
(a) inverted 
(b) colourful
(c) upright 
(d) all of these
Answer:
(a) inverted 

Question 5. 
Shadow are shortest in the:
(a) Morning 
(b) Evening
(c) Noon 
(d) None of these
Answer: 
(c) Noon 

Fill in the Blanks

Question 1. 
An object that gives out the light of their own are called ...............
Answer:
luminous object

Question 2. 
A thin sheet of plastic is an example of ............... object.
Answer:
translucent

Question 3. 
By shadows, we know about ............... of objects.
Answer:
shape

Question 4.  
............... object makes shadows.
Answer:
Opaque

Question 5. 
Pinhole camera produces ............... images.
Answer:
inverted

Question 6. 
Moon reflects ...............  light that falls on it.
Answer:
sun

Question 7. 
When opaque objects obstruct the light then ............... is formed.
Answer: 
shadow

State whether True or False

Question 1. 
Light travels in a straight line.
Answer:
True

Question 2. 
Image and shadows are similar.
Answer:
False

Question 3. 
When the direction of a source of light is changed, the shape of shadows change.
Answer:
True

Question 4. 
Bouncing back of light from a reflecting surface is called reflection of light.
Answer:
True

Question 5. 
The letters I, O, U will not show lateral inversion.
Answer:
True

 

Match the followings

Column I	Column II
1. Pinhole camera	(a) non-luminous object
2. Rectilinear motion	(b) emits light
3. Eraser	(c) surface on which image is formed
4. Butter paper	(d) opaque object
5. Mirror	(e) creates inverted image
6. Lateral inversion	(f) luminous body
7. Sun	(g) reflects the light that falls on it
8. Screen	(h) light travels in the straight line
9. Fire	(i) changes images from left to right
10. Chair	(j) transluœnt object

Answer:

Column I	Column II
1. Pinhole camera	(e) creates inverted image
2. Rectilinear motion	(h) light travels in the straight line
3. Eraser	(d) opaque object
4. Butter paper	(j) transluœnt object
5. Mirror	(g) reflects the light that falls on it
6. Lateral inversion	(i) changes images from left to right
7. Sun	(f) luminous body
8. Screen	(c) surface on which image is formed
9. Fire	(b) emits light
10. Chair	(a) non-luminous object

Very Short Answer Type Questions

Question 1. 
What is light?
Answer: 
Light is a form of energy which helps us in seeing objects.

Question 2. 
Suppose you go inside a completely dark room. Are you able to see any object in the room? If no, why? 
Answer: 
No, we will not be able to see the objects because we can see the objects only in the presence of light.

Question 3. 
What type of objects do not form shadows? Give reason.
Answer: 
Transparent and some translucent objects do not cast shadow because light pass through them.

Question 4. 
What is periscope?
Answer: 
Periscope is an optical device by which we can see objects located above our line of sight.

Question 5. 
Do the direction of the shadow change with the position of sun?
Answer: 
Yes, the direction of the shadow changes with the position of sun as the shadow is always formed opposite to the light.

Question 6. 
State the principle on which pinhole camera works.
Answer: 
The principle states that the light travels in a straight line.

Question 7. 
Give example of a natural pinhole camera.
Answer:
The image of sun can be seen through a dense tree when the ray of light travels through the gaps between the leaves.

Question 8. 
Why polished surface cause glare in our eyes? 
Answer: 
Polished surfaces produce regular reflection of light which is why it causes glare in our eyes.

 

Question 9. 
What is lateral inversion?
Answer: 
When an object is placed in front of a plane mirror, the right side of the object appears to be on the left side of the object and vice versa.

Question 10. 
Why we should not look directly on Sun?
Answer: 
We should not look directly at Sun because that could be extremely harmful to our eyes.

Short Answer Type Questions 

Question 1. 
The moon appears bright. Is it a luminous or non-luminous body?
Answer: 
The moon appears bright because it reflects the light that it gets from Sim via Earth. As it does not emit its own light so it is a non-luminous body.

Question 2. 
Give an example of each:
(a) Opaque and luminous.
(b) Translucent and luminous.
Answer:
(a) Opaque and luminous: Sun.
(b) Translucent and luminous: Flame of the lamp.

Question 3. 
Give an example of each:
(a) Transparent and non-luminous objects.
(b) Translucent and non-luminous objects.
Answer:
(a) Transparent and non-luminous objects: Air and water.
(b) Translucent and non-luminous objects: Polythene and smoke.

Question 4. 
Why is shadow formed when an opaque object comes in the path of light?
Answer: 
Light travels in a straight line since light cannot pass through the opaque objects, it creates a dark area around the object. This dark portion or area created on the screen is called a shadow.

Question 5. 
Can we get different shapes of shadows of the same objects? Does it depend on the colour of an object? Answer: Yes, by changing the direction of the source of light, the shapes of the shadow can be changed. Shadow does not depend on the colour of an object. Shadows are always black.

Question 6. 
What is pinhole camera?
Answer: 
A pinhole camera is a simple device that is constructed to demonstrate formation of image of an object with the help of light on the screen.

Question 7. 
what is a solar eclipse or how is solar eclipse formed?
Answer: 
When the Moon passes between the Sun and Earth, i.e. when the shadow of the Moon falls on the Earth, solar eclipse occurs. 

Long Answer Type Questions

Question 1. 
What is the difference between luminous and non-luminous objects? 
Answer: 
Difference between luminous and non-luminous objects

Luminous	Non-luminous
The objects that emit light of their own are called luminous objects.	The objects that do not emit light of their own are called non-luminous objects.
For example, Sun, bulb, lamp, etc.	For example, Moon, Earth, table, chair, etc.

Question 2. 
Distinguish between transparent, translucent and opaque materials. 
Answer: 
Difference between transparent, translucent and opaque materials

Transparent	Translucent	Opaque
1. Objects that allow light to pass through them completely are known as transparent.	Objects that allow light to pass through them partially are known as translucent.	Objects that do not allow light to pass through them are known as opaque.
2. Through transparent objects, we are able to see clearly.	Butter paper and thin plastic sheets are the examples of translucent objects.	Wax paper
3. Glass and water are the examples of transparent objects.	Through translucent objects, we are not able to see clearly.	Through opaque objects, we cannot see anything.

Question 3. 
Why do the size and shape of shadows change?
Answer: 
The size and shape of the shadow depend upon the distance and angle of the source of light from an object. As the light moves towards an opaque object, the shadow becomes larger. As the light moves away from an opaque object, the shadow becomes smaller. The shape of the shadow also changes with an angle if the angle of light falls on  the object is smaller, the shadow is longer and when the angle of light is larger, the shadow is shorter.

 

Question 4. 
What is needed to make a shadow? Answer: To obtain shadow we need following things:

1. Some objects which do not allow light to pass through them i.e. opaque materials.
2. Source of light.
3. A screen-like ground, walls of the room, etc.

Question 5. 
Why do we get an inverted image in the pinhole camera? 
Answer:

Light always travels in a straight line. The light from the top of an. object travels in a straight line and reaches at the bottom of the screen as shown in figure and rays from the bottom of an object reaches at the top of the screen. Hence, the image looks inverted. 

Question 6. 
Differentiate between shadow and image. 
Answer: 
Differences between shadow and image are:

Shadow	Image
Shadow is formed when an opaque object is placed in the path of the light.	Image is formed due to the reflection of light.
Shadow is dark only.	Images are colourful.
Shadow gives us information about shapes of objects.	Actual picture of an object can be seen.