Ot u.ivm. assuming are mass central at cm + k.e. about c.m. total energy prove that +ve total energy for a system of particle is constant if the external forces

OT U.IVM. assuming are mass central at CM + K.E. about C.M. Total Energy Prove that +ve total energy for a system of particle is constant if the external forces are derivable from a scalar potential function and if the internal forces are central.