how earth moves g3
TRANSCRIPT
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How Earth Moves
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Ch.8 Lesson 4How Earth Moves
• ( Objectives )• The student be able to :• 1-Explore and make a model of
Earth to show how sun shines on it.
• 2-Understand that Earth rotates on its axis and this cause day and night.
• 3-Understand that Earth revolution causes the seasons.
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
What causes Day and Night?• It seems as if the Sun is
always moving across the sky.
• It looks as if the Sun rises in the East and sets in the West.
• But The Sun doesn’t move.
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
* Earth is shaped like a ball.This shape is called a sphere• Earth rotates = turn• Earth rotation causes day
and night.
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
• As Earth rotates, there is daylight where Earth faces the Sun.
• And darkness where Earth is turned away from the Sun.
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
It takes 24 hours for Earth to make one complete rotation.one complete rotation= 1 dayA day is made up of hours of light + hours of dark.
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
Earth spins or rotates around its axis. is an imaginary line through the center of Earth From the North pole to the South pole.* It is slightly Tilted.
(Vocabulary):sphereRotatesAxisRevolveOrbit
axis
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Ch.8 Lesson 4How Earth Moves
The tilt of Earth changes how the Sun’s rays strike the surface.• At the poles the Sun
stays low in the sky during the day the Sun’s rays are weak it is cold
• At the equator the Sun rises high in the sky the Sun’s rays are stronger
• Temperature is higher.
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
What causes Seasons?• Earth also revolves
around the Sun. when an object moves around another object.
(Vocabulary):sphereRotatesAxisRevolveOrbit
revolves
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Ch.8 Lesson 4How Earth Moves
Earth travels in a regular path called orbit is the path that an object follows as it revolves around another object.It takes 365 ¼ days for Earth to make 1 complete revolution around the Sun.
(Vocabulary):sphereRotatesAxisRevolveOrbit
Orbit
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Ch.8 Lesson 4How Earth Moves
In many parts of the world, the year made up of 4 seasons.
Why?Because of the Earth’s tilted axis.
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
* Having a tilted axis means Earth slants a little as it revolves around the Sun.• Earth is always tilted in
the same direction.• As Earth travels around
the Sun, the part tilted toward the Sun changes.
•
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
When the North pole tilted toward the Sun the Sun travels higher in sky . It is Summer.
When the North pole tilted away from the Sun the Sun travels lower in sky . It is Winter
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
What about Fall and Spring?.The North Pole is tilted neither toward nor away from the Sun.
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
How Does the Sun’s Path in the Sky Change ?During the Summer your part of Earth tilted toward the Sun The Sun’s path appears higher in the sky.During the Winter your part of Earth tilted away from the Sun The Sun’s path appears lower in the sky.
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
The Sun in the Summer and Winter Skies:
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Ch.8 Lesson 4How Earth Moves
( Check for Understanding)1-Describe the motion of Earth that makes 1 day.2-What would happen to the seasons if Earth’s axis is not tilted?3-How are rotation and revolution are different?
(Vocabulary):sphereRotatesAxisRevolveOrbit
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Rotating Revolving
Moving of Earth around itself through its axis.
Moving of Earth in its orbit around the Sun.
It takes 24 hours or 1 day
It takes 365 ¼ days or 1 year
It causes day and night.
It causes the 4 seasons.