Question 196: Work, Energy and Power & Circular Motion

Question

A uniform chain of length $$2$$ $$m$$ is kept on a table such that a length of $$60$$ $$cm$$ hangs freely from the edge of  the table. The total mass of the chain is $$4$$ $$kg.$$ What is the work done in pulling the entire chain on the table?

Accepted Answer

Mass of hanging part $$(m') = {4 \over 2} 	imes \left( {0.6} ight)kg$$ = 1.2 kg
Let at the surface $$PE=0$$
Center of mass of hanging part $$=0.3$$ $$m$$ below the surface of the table
$${U_i} =  - m'gx =  - 1.2 	imes 10 	imes 0.30$$ = - 3.6 J
$$\Delta U = m'gx = 3.6 J = $$ Work done in putting the entire chain on the table.

Answer

$$12$$ $$J$$

Answer

$$3.6$$  $$J$$

Answer

$$7.2$$ $$J$$

Answer

$$1200$$ $$J$$

Work, Energy and Power & Circular Motion

A uniform chain of length $2 m is kept on a table such that a length of 60 cm hangs freely from the edge of the table. The total mass of the chain is 4 kg.$ What is the work done in pulling the entire chain on the table?

Choose the correct answer: