A particle of mass m is moving in a horizontal circle of radius r under a centripetal force equal to -K/r2 , where K is a constant. The total energy of the particle is
Here mv2r = Kr2 ∴K.E. = 12mv2 = K2r
U = −∫r∞F dr = −∫r∞(−Kr2)dr = −Kr
Total energy E = K.E. + P.E. = K2r − Kr = −K2r