- #1
deep838
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Homework Statement
A chain of mass 4Kg and length 2m is lying on a table, such that 60 cm of one end is hanging from one edge off the table. Find the work done to pull the entire chain on the table.
Homework Equations
(anything that'll work i suppose)
The Attempt at a Solution
I thought that the work done to do this is simply the work done against gravity to lift the hanging mass.
The mass per unit length of the chain is λ=m/l=2Kg/m
So the mass of the hanging portion is λ*60cm=2*0.6Kg=1.2Kg
So the work done to lift it 0.6m up is 1.2*9.8*0.6J=7.056J
But the given answer is 3.6J.
What am I doing wrong?