Embibe Experts Solutions for Chapter: Friction, Exercise 4: Exercise-4

The coefficient of static and kinetic friction between the two blocks and also between the lower block and the ground are ${\mu }_s=0.6$ and ${\mu }_k=0.4$. Find the value of tension $T$ applied on the lower block at which the upper block begins to slip relative to lower block.

A block of mass $m$ rests on a horizontal floor with which it has a coefficient of static friction $\mu$. It is desired to make the body move by applying the minimum possible force $F$. Find the magnitude of $F$ and the direction in which it has to be applied.

The member $OA$ rotates in vertical plane about a horizontal axis through $O$ with a constant counter clockwise velocity $\omega =3 \mathrm{rad} {\mathrm{s}}^{-1}$. As it passes the position $\theta =0$, a small mass $m$ is placed upon it at a radial distance $r=0.5\mathrm{m}$. If the mass is observed to slip at $\theta =37°$, find the coefficient of friction between the mass & the member.