Q. As pluto moves from the perihelion to-the aphelion, the work done by gravitational pull of Sun on Pluto is

 1971  233 Gravitation Report Error

Solution:

As gravity is an attractive force and acts towards the centre of sun.Now taking Pluto from the perihelion to the aphelion means it is moving away from Sun,thus from implies that work done by gravitational force has to be negative.