A uniform chain has a mass ' m ' and length l '. It is held on a frictionless table with one-sisth of its length hanging over the edge. The work done in just pulling the hanging part back on the table is:

Step-by-step solution

Work done in pulling the hanging par of chain on table is equal to gain in potential energy, W = M g h Mass of hanging part which is 1 6 th   of the total length, given that mass of chain is m   is m 6 . Centre of mass is located at a distance l 12   from the table. ∴ W = m 6 g l 12 ⇒ W = m g l 72