Extra 30 short questions and answers from Chapter:11 Light, Shadows, and Reflections of Class 6 Science (CBSE):-
What is light?
Answer:
Light is a form of energy that enables us to see objects. It travels in a straight line and is essential for vision.
What are luminous and non-luminous objects? Give examples.
Answer:
Luminous objects
: Objects that emit their own light (e.g., Sun, candle, bulb).
Non-luminous objects
: Objects that do not emit their own light but can be seen when light falls on them (e.g., table, book, moon).
What are transparent, translucent, and opaque objects?
Answer:
Transparent objects
allow light to pass through completely (e.g., glass).
Translucent objects
allow light to pass partially (e.g., frosted glass).
Opaque objects
do not allow light to pass through (e.g., wood, metal).
Why does a shadow form?
Answer:
A shadow forms when an opaque object blocks the path of light, preventing light from reaching a surface.
Why are shadows always black?
Answer:
Shadows are black because they are formed in the absence of light. The object blocks light, preventing
colours
from reaching the surface.
What are the two main factors that affect the size of a shadow?
Answer:
Distance between the object and the light source.
Angle and position of the light source.
Why does a shadow change its size during the day?
Answer:
The Sun changes its position in the sky. In the morning and evening, shadows are long, while at noon, when the Sun is directly overhead, shadows are short.
What is reflection?
Answer:
Reflection is the bouncing back of light when it strikes a smooth and shiny surface, such as a mirror.
How does a plane mirror form an image?
Answer:
A plane mirror forms a
virtual, erect, and laterally inverted
image of the object placed in front of it.
What is lateral inversion?
Answer:
Lateral inversion is the phenomenon where the left side of an object appears as the right side in a mirror and vice versa.
What is a pinhole camera?
Answer:
A pinhole camera is a simple device with a small hole that forms an
inverted and smaller
image of an object on a screen.
What happens when an object is moved closer to a light source?
Answer:
The shadow becomes larger and sharper as the object blocks
more light
.
What happens when the light source moves farther from an object?
Answer:
The shadow becomes smaller and less sharp as the object blocks less light.
Why do we see the moon even though it is a non-luminous object?
Answer:
The moon reflects sunlight, making it visible to us at night.
Can a transparent object form a shadow? Why or why not?
Answer:
No, a transparent object does not form a shadow because it allows light to pass through completely.
What are the characteristics of a shadow?
Answer:
It is always black.
It forms on the opposite side of the light source.
Its shape depends on the object’s shape.
How does a rough surface reflect light?
Answer:
A rough surface reflects light irregularly in different directions, causing
diffused reflection
.
Why do we see objects?
Answer:
We see objects because light from a luminous source falls on them and is reflected into our eyes.
What type of image does a pinhole camera form?
Answer:
A pinhole camera forms an
inverted, real, and smaller
image of an object.
How does a mirror differ from a shadow?
Answer:
A
mirror
forms a
clear,
coloured
, and laterally inverted
image.
A
shadow
is
black and has no details
of the object.
Can a shadow be
coloured
? Why or why not?
Answer:
No, shadows are always black because they are formed due to the absence of light.
Why do stars appear to shine at night?
Answer:
Stars are luminous objects that emit their own light, making them visible at night.
Why does an image in a mirror appear reversed?
Answer:
The image in a mirror appears reversed due to
lateral inversion
, where the left appears as right and vice versa.
What are the differences between real and virtual images?
Answer:
Real Image
: Formed on a screen, inverted.
Virtual Image
: Cannot be captured on a screen, erect.
What happens when a torch is pointed towards a wall?
Answer:
An object placed between the torch and the wall will form a shadow on the wall.
Why is a plane mirror used in periscopes?
Answer:
A plane mirror reflects light without distorting the image, making it useful in periscopes for seeing around corners
.
What is the difference between an image and a shadow?
Answer:
An
image
is formed by reflected light and shows details.
A
shadow
is a dark region formed due to blocked light and has no details.
How does the angle of a light source affect a shadow?
Answer:
When the light source is at a low angle, shadows are long. When the light is overhead, shadows are short.
Can a shadow be smaller than the object? When?
Answer:
Yes, when the light source is far from the object, the shadow appears smaller.
Why do we use mirrors in torches and headlights?
Answer:
Mirrors reflect and focus light in a specific direction, increasing brightness and visibility.
