Variations in the length of daytime and nighttime from season to seaso...
Explanation:
The variation in the length of daytime and nighttime from season to season is due to the revolution of the earth on a tilted axis. The earth's axis is tilted at an angle of 23.5 degrees with respect to the plane of its orbit around the Sun. This tilt causes different parts of the earth to receive varying amounts of sunlight at different times of the year.
Effect on Seasons:
As the earth revolves around the Sun, the tilt of its axis causes different hemispheres of the earth to be tilted towards or away from the Sun at different times of the year. When the northern hemisphere is tilted towards the Sun, it experiences summer, while the southern hemisphere experiences winter. Similarly, when the northern hemisphere is tilted away from the Sun, it experiences winter, while the southern hemisphere experiences summer.
Effect on Day and Night:
The tilt of the earth's axis also affects the length of daytime and nighttime. During the summer solstice, which occurs around June 21st, the northern hemisphere is tilted towards the Sun, resulting in longer days and shorter nights. Conversely, during the winter solstice, which occurs around December 21st, the northern hemisphere is tilted away from the Sun, resulting in shorter days and longer nights.
Effect on Equinoxes:
During the spring and fall equinoxes, which occur around March 20th and September 22nd respectively, the tilt of the earth's axis is neither towards nor away from the Sun. This results in equal amounts of daylight and nighttime all over the earth.
Conclusion:
Therefore, the variation in the length of daytime and nighttime from season to season is due to the revolution of the earth on a tilted axis. This tilt causes different parts of the earth to receive varying amounts of sunlight at different times of the year, resulting in the changing seasons and the length of daylight and nighttime.
Variations in the length of daytime and nighttime from season to seaso...
our earth is revolving around the sun in an elliptical orbit,and one complete revolution around the sun takes the time period of one year. During this one year long revolution process,the distance between earth and sun changes continuously, because the there is no constant diameter of the elliptical orbit. And this changes of distance are the main reason behind the change of daytime and nighttime expansions.
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