CBSE Class 11-science Answered

Gravitational potential energy is the energy possessed by a body by virtue of its position w.r.t the gravitational field , that is its height. If the object is at ground level, it posess only potential energy. If the obejct is kept at certain height, say, a ball is kept high on the shelf, it has gravitsational potential energy. Water at a height falls down, gravitational energy of the water is changed into its kinetic energy. There is some amount of work doen in bringing the object against gravity to its height, so the gravitational energy is given a - sign.