Question
Physics Question on work
A uniform chain of length L and mass M is lying on a smooth table and one-third of its length is hanging vertically down over the edge of the table. If g is the acceleration due to gravity, the work required to pull the hanging part on to the table is:
A
18MgL
B
9MgL
C
3MgL
D
MgL
Answer
18MgL
Explanation
Solution
There will be the change in position of centre of gravity, which was L/6 down now is shifted to the top of table hence, Work done =3M×g×6L=18MgL