Question

why are days and nights equal on march 21

Answer 1

Days and nights are equal at all places on earth on March 21st because the sun rays falls vertically on equator and the circle of illumination passes through both the poles...

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Answer 2

March 21 and September 23 are popularly known as equinox, the day when days and nights are equal in length bcoz the earth's equator passes through the center of the sun.


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