Question

A uniform chain of length 'l' is placed on a rough table, with its length ln(n>1) hanging over the edge of the table. If the chain just begins to slide off the table by itself, the coefficient of friction between the chain and the table is :

Answer 1

Explanation:

In this case, the weight of the hanging part must be just equal to the frictional force acting on the part on the table.

We know that, F=μN

Let linear mass density be γ.

Mass of the chain on the table is m

′

=l(1−

n

1

)γ

Frictional force, μN=μγ(l−

n

l

)g, where, γ is the linear mass density of the chain.

Weight of the hanging part, W=γ

n

l

g

Equating the above two equations yield,

μ=

n−1

1