At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga.
Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus.
Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
Total Mechanical Energy = Potential Energy + Kinetic Energy
Although PE and KE change their sum ME remains constant irrespective of the position of the bob, during the motion of the pendulum.
hmm..without any friction the total sum i.e mechanical energy would still remain same but constant and there would be no losses ..as bob moves to its highest potential its KE gets converted to PE and as it is at its reference position the PE gets converted to max KE or i could say you can see the the bob with it highest VELOCITY it can achieve during its swinging period ..but as i said no losses the pendulum won't stop swinging.. it would move indefinitely until an external force such as friction is appiled..!!
hope this would help ..
correct me if i am wrong..:)