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Revolution of the earth
The earth’s revolution refers to the movement of the earth around the sun following its orbit. The speed of revolution is about 29.6 kilometres per second.
The earth revolves around the sun for approximately 365 days a year. Anormal year has 365 days. The fraction days are not counted every year but is added once in 4 years to make a leap year of 366 days.
The leap year occurs once in every four years, when February has 29 days instead of 28.
Effects of the Earth’s revolution
The revolution of the earth around the sun and tilting on its axis have the following effects:
(1) Seasons
A season is the main period of the year with a particular type of weather. Seasons are caused by the inclination of the earth’s axis and the earth’s revolution around the sun.
The earth’s axis is tilted at an angle of 66%° to the earth’s orbital plane and it is always pointing to the same direction in space. In its
revolution around the sun, one of the hemispheres is inclined towards the sun at one period of the year and away from it at another period of the year.
For example, in June, July and August, the northern hemisphere tilts towards the sun, thus, it is Summer time. The same months in the southern hemisphere. it is Winter because the southern hemisphere tilts away from the sun. Spring and Autumn are short seasonal transitions between Summer and Winter, respectively.
Generally, there are four seasons in a year that are differentiated by temperature and rainfall characteristics. These seasons are Summer, Autumn,
Winter and Spring.
The four seasons are more pronounced in areas found between 23% and 6612e of latitude north and south of the equator.
Around 0° to 5e north and south of the equator, there would be no season because it experiences high temperature and rainfall throughout the year and the sun is almost overhead at those places throughout the year.
However, due to variations in relief, seasonal variations are experienced.
FORM FOUR SPECIAL EXAMINATION SERIES ONE (REGISTRATION) 2025