[2] ative [2] e the inetic [2] 44. 2072 Supp Q.No. 5a 2069 Set B Q.No. 5a 2069 Set B Old Q.No. 2a 2057 Q.No. 2a What is the principle of conservation of energy? Show that total mechanical energy of a body is conserved when it moves under the action of gravitational field. [4]?​