Earthing

A tunnel is dug across the diameter of earth. A ball is released from the surface of Earth into the tunnel. The velocity of ball when it is at a distance (R )/(2) from centre of earth is (where R = radius of Earth and M = mass of Earth)

Draw a diagram showing the orbit of Earth and the orbit of Earth's Moon. Label the Sun, Earth, the Moon, Earths' orbit, and the Moon's orbit.

Earth is. a/an

Earth is an

Assertion :-The geological history of earth closely correlates with the biological history of earth. Reason :- Earth is very old.