If suddenly the gravitational force of attraction between Earth and a satellite revolving around it becomes zero, then the satellite will

The escape velocity of a body depends upon mass as

Energy required to move a body of mass $$m$$ from an orbit of radius $$2R$$ to $$3R$$ is

A spring of force constant $$800$$ $$N/m$$ has an extension of $$5$$ $$cm.$$ The work done in extending it from $$5$$ $$cm$$ to $$15$$ $$cm$$ is