The document discusses the rotation and revolution of Earth and their effects. It notes that Earth rotates on its axis in a counter-clockwise direction over 24 hours, causing day and night. Earth also revolves around the sun in an elliptical orbit over approximately 1 year, resulting in varying lengths of day and causing the changing of seasons. Specifically, it explains that summer solstice occurs when the North Pole is tilted toward the sun, winter solstice when it is tilted away, and equinoxes when sunlight is equal between hemispheres.

1. Presented By:
Prachi Pathak

3. • Earth rotates
around its AXIS.
• The direction of our
rotation
is COUNTER
CLOCKWISE.
• The period of
rotation for Earth is
24 hours, meaning
we rotate at a rate
of about 15 degrees
per hour.
ROTATION

4. EFFECTS OF ROTATION
Day and night
Bulging at equator
Flattening of poles
Deflection of wind and ocean currents
Tides
Apparent movement

5. NIGHT

7. REVOLUTION
• Revolution is the
movement of one object
around another object.
• Earth revolves around the Sun in an elliptical orbit,
just as the Moon revolves around the Earth in an
elliptical orbit.
• We revolve around the sun in a counter-
clockwise direction
• The rate of revolution is about 1 degree per day

8. EFFECT OF EARTH’S REVOLUTION
23 SEPTEMBER
21 JUNE
21 MARCH
22 DECEMBER
Varying lenghths
of day and night
Changing
seasons

9. What is Summer solistice?
• The Earth’s axis is tilted by 23.4 degrees and so
the plane of the Earth’s equator is tilted with
respect to the plane of the Earth’s orbit around
the Sun – sometimes referred to as the ecliptic.
• During the Northern Hemisphere summer, the
Sun illuminates the Northern Hemisphere more
than the Southern Hemisphere.
• During this time we receive more hours of
sunlight and the longest day is known as the
summer solstice

10. What is winter solistice?
• During the winter, the Sun illuminates the
Southern Hemisphere more than the Northern
Hemisphere because the North Pole is titled
away from the Sun.
• During this time we receive fewer hours of
sunlight and the shortest day (and longest
night) is known as the winter solstice

11. What is equinox?
• At two points in the year the Sun will
illuminate the Northern and Southern
Hemispheres equally – these are known as the
equinoxes
• The autumnal equinox in September
• The vernal/Spring equinox in March.

13. FOUR SEASONS

14. The cycle of seasons is caused by Earth's tilt
toward the sun