Question

Give reason : A rocket fired upwards goes into the space despite the gravitational pull of Earth .

Answer 1

This is because of something called escape velocity .

Escape velocity is  the velocity at which an object must travel in order to escape from the gravitational force of the earth . At this velocity, the earth's gravitational pull loses it influence on the object .The escape velocity of earth is 11.186 km / s.  So the rockets must be fired at a velocity more than the escape velocity .

Escape velocity varies from planet to planet . It is directly proportional to the mass of the planet .