A chain is placed on smooth table with (1)/(4)th of its length hanging over the edge. If the length is 2 m and weight is 4 kg, the energy needed to pull it back to the surface of table is (g = 10ms^(-2)):

A chain is placed on smooth table with (1)/(4)th of its length hanging

1.	A chain is placed on smooth table with (1)/(4)th of its length hanging over the edge. If the length is 2 m and weight is 4 kg, the energy needed to pull it back to the surface of table is (g = 10ms^(-2)):
Answer» 0.25 J 2.5 J 25 J 50 J Solution :When `1/n`th PART of the chain is hanging from the edge then work DONE to pull the chain on table is `W=(mgl)/(2N^(2))=(mgl)/(2xx(4)^(2))=(mgl)/(32)=(4xx10xx2)/(2)` W=2.5 J.

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A chain is placed on smooth table with (1)/(4)th of its length hanging over the edge. If the length is 2 m and weight is 4 kg, the energy needed to pull it back to the surface of table is (g = 10ms^(-2)):

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