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Light and shadows - Coggle Diagram
Light and shadows
how light enables us to see things
can only see the objects when light from this object en6ters our eyes
how light from objects can enter our eyes
The objects is a source of light
the object reflected light from a light source into your eye
when an object is alight source and give off light that enters our eye
allows us to see the object directly
objects that cannot give off light must reflect light from other lights source to enter our eyes
example
in a dark room we cannot see a table and chair but once we turn on the lamp we can see it because the table and chair reflect light from the lamp into our eyes
reflection of lights
enables us to see images of objects in the mirror
how does it work
light from the surrounding object is reflected onto the mirror
light is then reflected by mirror and enters our eye
this enables us to see images of objects in the mirror
Periscope
mirrors arranged in certain a way so it allows us to see objects that are outside our sight
how does it work
the objects first reflects light from the surrounding onto the first mirror
first mirror reflects the light onto the second mirror
second mirror reflects the light to enter out eyes for us to see the image of an objects
how light passes through different material
Not all materials allow the same amount of light to pass through
main group of materials allows different amount of light to pass through
translucent
allows some light to pass through cannot see through it clearly(objects on the opposite side might seem blurry)
opaque
does not allow light to pass through it cannot see through it(object on the oppsite side cannot be seen at all)
transparent
allows most amount of light to pass through can see clearly(object is more clear)
examples of each materials
translucent
frosted glass
tracing paper
cloth
some kind of platics
opaque
wood
rubber
metals
clay
transparent
clear plastic
air
glass
drinking water
you can measure how much light a material allows to pass through by using a light sensor and data logger
when conducting an experiment to find out the amount of light passing through an object with a light sensor
SHOULD ALWAYS BE CONDUCTED IN A DARK PLACE
ensure no other light from other light source will be detected by the light sensor
as other light source being detected by the light sensor will affect the results
thickness of materials also affects the amount of light that passes through
the thicker the material the less light is allowed to pass through it
How shadows are formed
When light is blocked by and object
characteristic of shadows
Always form on the opposite side on the light source
Shape of shadow is always similar to the shape of the object
Not all objects can produce shadows
only this
translucent
allows some light to pass throught produces light shadows
opaque
does not allow light to pass through produces dark shadows
objects that cant
transparent
allows most light to pass through forms no shadow
When light is blocked by an opaque objects it form a dark shadow
a screen (or place where the shadow is formed ) is opaque dark shadows can be formed on it
introduction to light
A form of energy
helps us to see things around our surroundings
example
Line could be see at point X when the hole of 3 cardboard are line up in a straight line
but when 1 of the hole of the cardboard is not arranged in a straight line with the other cardboard hole the light cannot be seen from point X
travels in a straight line
sources of light
objects that can give off their own light
stars
sun
fireflies
fuels
only when their burning
electric bulb
torch light
lamp
only works when turned on
ways to change shapes and sizes of shadow