//Bullet 
//refer fig. 17.15
//Initial momentum of the system=Final momentum
v=21.31  //m/sec
//Kinetic Energy lost= Initial K.E- Final K.E
loss=((0.5*400^2)/(9.81*2)+(30*15^2)/(2*9.81))-((30.5*21.31^2)/(2*9.81))  //J
printf("\nLoss of energy=%.3f J",loss)