Question

If one third of the length of a uniform chain of mass 10 kg and length 18 m is hanging at the edge of a table, the work done to pull the hanging part onto the table is 198 2) 130.6 J 3) 260 J 4) 0​

Answer 1

Length of hanging chaing is l/3 , and mass of hanging chain is M=m/3.

The center of mass of hanging chain is at h=

2l/3=6/from the table top

So work done ,W=Mgh= 3x6 mgl =18 mgl