If a planet of given density were made larger, its force of attraction for an object on its surface would increase because of planet's greater mass but would decrease because of greater separation from the object to the centre of the planet. Which effect predominates?
Increase in radius
Increase in mass
Both affect the attraction equally
None of the above
If were doubled Mass becomes 8 times as
Force due to increase in mass increases 8 times and due to increase in radius force reduces 4 times. Therefore, the effect of increase of mass predominates.
Hence option 2 is correct.