The earth has two types of motions, namely rotation and revolution. Rotation is the movement of the earth on its axis. The movement of the earth around the sun in a fixed path or orbit is called Revolution.
1. What is the angle of inclination of the earth's axis with its orbital plane?
The angle of inclination of the earth's axis is 66 1/2 with its orbital plane.
2. Define Rotation and Revolution?
Rotation is the movement of earth on its axis. Revolution is the movement of the earth around the sun on a fixed orbit.
3. What is a leap year?
The earth revolves around the sun for 365 days and 6 hours. For our convenience, we count only 365 days. So after every 4 years, when 24 hours get completed we add the time as additional day in February which is of 29 days. Thus every fourth year is known as leap year.
4. What is an equinox?
On 21st March and 23rd September, direct rays of sun fall on the equator. During this position, neither of the poles is tilted towards the sun due to which the whole earth experiences equal days and equal nights. This is known as an equinox.
5. What is circle of illumination?
The circle that divides the day from night on the globe is called the circle of illumination.
6. What is axis?
The imaginary line which passes from the centre of the earth and joins the two poles namely North Pole and South Pole is known as axis.