Question

A rope of mass m and length l lies on a frictionless table with a short portion

Answer 1

given L/3 part of rope is hangingwe have to solve using integration methods, lets say 'x' part of rope is consided with an element 'dx' which is pulled up withlimits from 0 to L/3Potential energy = mghhere dE= integral of ( Mx/L*g*dx) E = integral of ( M/L*g*x.dx) limits from 0 to L/3 P.E = MgL/18

Answer 2

ANSWER IS IN THE IMAGE