A uniform chain of length L is lying partly on a table the remaining part hanging down from the edge of the table. If the coefficient of friction between the chain and the table is 0.5, what is the minimum length of the chain that should lie on the table, to prevent the chain from slipping down to the ground ?

Options

A. `L//3`
B. `L//2`
C. `2L//3`
D. `3L//4`

Answer

c

Explanation

The fraction of length of chain that can be hung safely from the edge of table is
`(l)/(L)=(mu)/(mu+1)=(0.5)/(0.5+1)=(1)/(3)`
`:.(l)/(L)=(1)/(3)impliesl=(L)/(3)`
:. Minimum length of chain that lies on the table is
`L-l=L-(L)/(3)=(2L)/(3)`
So correct choice is (c).