A block pressed against the vertical wall is in equilibrium. The minimum coefficient of  friction is:-

A uniform chain of $6\, m$ length is placed on a table such that a part of its length is hanging over the edge of the table. The system is at rest. The co-efficient of static friction between the chain and the surface of the table is $0.5$, the maximum length of the chain hanging from the table is.......$m.$

The coefficient of friction $\mu $ and the angle of friction $\lambda $ are related as

When a body slides down from rest along a smooth inclined plane making an angle of $45^o$ with the horizontal, it takes time $T$. When the same body slides down from rest along a rough inclined plane making the same angle and through the same distance, it is seen to take time $pT$, where $p$ is some number greater than $1$. Calculate the coefficient of friction between the body and the rough plane.

A force of $19.6\, N$ when applied parallel to the surface just moves a body of mass $10 \,kg$ kept on a horizontal surface. If a $5\, kg$ mass is kept on the first mass, the force applied parallel to the surface to just move the combined body is........ $N.$ 

If for an inclined plane coefficient of static friction is ${\mu _s} = \frac{3}{4}$, then for the inclined plane angle of repose will be ........ $^o$