The document discusses the motion of the Earth and how it causes day and night. It explains that the Earth rotates on its axis every 24 hours, which causes the apparent rising and setting of the sun. As the Earth rotates, different sides face the sun, creating day on one side and night on the other. It also discusses how the Earth revolves around the sun once every 365 days, and how this and the rotation of the Earth cause shadows to appear in different positions at different times of day.

2. - We used to believe that the sun is moving as
it rises from the east & sets from the west.
-But the fact is the sun is not moving at all,
the earth is the one that is moving.

3. - The earth rotate “spins” around itself “its axis”
every day “24 hours”.
- And this rotation causes “the day & night” on
earth ,because as the earth is rotating around
itself, one side will be facing the sun so it will
have day, while the other side will be far from
the sun so it will have night .

4. - The Earth rotates around its axis “itself”
every 24 hours “day”.
- This rotation causes the “day & night” on
earth.
The Earth’s motion

5. “ When something appears to be moving”
The Apparent motion
Examples
-The sun appears to move , it
appears to rise from the east &
set to the west.
-The stars too appears to be
moving in the sky at night
Earth’s rotation causes apparent motion, but the sun and
stars are not moving in real/

6. Take a look at this picture
Have you ever
wonder what is
this dark area
standing beside
you?
It’s your shadow

7. - It’s the dark area that is formed
when the light is blocked by an
object.
What is the shadow?

8. But some times I saw my shadow
at different positions, How this
happens?
- This depends on the position of the sun,
as the earth move around its axis, the
position of the sun changes, that causes
the shadow to be found at different
positions.

9. Example
During the
early morning
Shadow is long
During the Mid
day
Shadow is short
During the
sunset
Shadow is long

10. - During the sun rise & the sunset:
The sun is at the sides of the tree, so a large
part of the tree blocks the sun light, so the
shadow is long.
-During the mid day:
The sun is above the tree, so only a
small part blocks
the sun light, so the shadow is short.

11. - The earth revolves around the sun.
- The earth completes one orbit around the
sun in 365 ¼ days.
The sun & the Earth
Revolution: When an object travels around another
object.
Orbit: It’s the path of the revolving object.
Earth
Orbit