light y 5

1. Light

2. Is light a type of energy ?
Can we see it or feel it ?

3. Sound is a type of energy
that we can hear, so sound is
a type of energy that we can
_________see

4. Light is made up of two energy :
Electric Magnetic
Electromagnetic

5. Light is a type of :
Transverse
waves
Longitudinal
waves

6. In which direction does the light
waves move ?
It moves in a straight line

7. How far is the earth from the sun ?
150 million kilometer

8. How many minutes does it take the
sunlight to reach the earth?
8 minutes

9. Light travels very fast that sunlight
takes only 8 minutes to reach the
earth although the distance is very
big between the earth and the sun
(150million kilometer)

10. Does light need a medium to travel ?
No
How come the particles of light energy
moves up and down ?

11. Can we feel the light energy ?
when you stand in sunlight .
Your body absorbs the energy
and you feel heat.

12. What will happen to our body if we
absorbed too much of that energy ?
If you absorb too much of that
energy , it harms your skin and
you get burnt.

13. Transparent
Materials that allows light to pass
through ( you can see through them ).

14. Translucent
Materials that allows only some amount of light
to pass through (you can’t see clearly through
them )

15. Opaque
Materials that don’t allow light to pass through
(you can’t see through them)

19. What are the sources of light ?

21. Light is
•Reflected or
•Absorbed or
•Passed

23. Reflection
• A mirror is not a source of light. It doesn't make
its own light, it just reflects light.
• The moon is not a source of light. It reflects light
from the Sun.
• You would not be able
to see a reflector of light
, such as a mirror, in
a completely
dark room.

24. Reflection
• It is the bouncing back of light from a surface
• If something is shiny , it reflects light
• If some thing is dull , it doesn’t reflect light
But the light is absorbed

25. How do you think we can see ?
Angle of falling light = angle of reflected light
Law of reflection

26. How do you think we can see ?
Light travels in straight lines.
When light hits an object, it
is reflected (bounces off)
and enters our eyes. This is
how we see the object.

28. • Smooth, shiny surfaces such as mirrors and
polished metals reflect light well. Dull and
dark surfaces such as dark fabrics do not
reflect light well.

29. Light absorption
• Some of the light energy that hits an object is
absorbed.
• -Objects of different colors absorb different
amounts of light. The light that is absorbed is
transformed into heat energy.
• - Darker objects absorb more light than lighter
object.

30. Light is passed
• Through a transparent material ex : glass

31. How is shadow formed ?
When light is blocked by an
opaque object

33. The size of the shadow depends on the
distance from the light source
Small shadow
Big shadow
Far from light source
Close to light source

34. Shadows made by sun

35. Silhouette
• An opaque object held between a
light source and a screen gives
you a shadow on the screen the
shadow on the screen . The
shadow of the object is the
silhouette .

37. Periscope

38. Periscope
• It is a device for seeing around corners or over
things.
• It is used to see what is happening on the
other side of a wall.

39. Position of the shadow depends on
the light source
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