Notes-Class 7-Geography-Chapter-1-How Seasons Occur-Part 1-Maharashtra Board

Rotation of the earth :

• The earth’s turning around its own axis is called rotation of the earth.
• It takes 24 hours for the earth to rotate around itself.
• It rotates from the west to the east.

• Day and night occur due to the Earth rotating on its axis.
• The part of earth which faces the sun, experiences day while part of earth away from Sun that gets no light, experiences night.

Measurement of time :

• The earth’s rotation has enabled us to measure time in terms of days.
• During a single day, we experience different stages like sunrise, midday, sunset as well as daytime and nighttime.

Revolution of the earth :

• The movement of the earth around the sun in a fixed path or orbit is called Revolution.
• Earth takes 365 days for one revolution.

The apparent change in the locations of the sunrise and the sunset :

• Everyday, the sun rises in the east and sets in the west.
• However, the locations of the sunrise and the sunset on the horizon keep on apparently changing.
• The position of the rising sun keeps on moving towards the south in the period from 21st June to 22nd December.
• From 22nd December to 21st June, the sun keeps on moving towards the north.