Which one of the following statements is incorrect?
Rolling friction is smaller than sliding friction.
Limiting value of static friction is directly proportional to normal reaction.
Coefficient of sliding friction has dimensions of length.
Frictional force opposes the relative motion.
A uniform chain of length $L$ which hanges partially from a table, is kept in equilibrium by friction. The maximum length that can withstand without slipping is $l$ , then coefficient of friction between the table and the chain is
A block of mass $15 \;kg$ is placed on a long trolley. The coefficient of static friction between the block and the trolley is $0.18$. The trolley accelerates from rest with $0.5 \;m s ^{-2}$ for $20 \;s$ and then moves with uniform velocity. Discuss the motion of the block as vlewed by
$(a)$ a stationary observer on the ground,
$(b)$ an observer moving with the trolley.
A body of mass $\mathrm{m}$ is kept on a rough horizontal surface (coefficient of friction $=\mu$ ) A horizontal force is applied on the body, but it does not move. The resultant of normal reaction and the frictional force acting on the object is given by $\mathrm{F},$ where $\mathrm{F}$ is
A block of mass $m$ rests on a rough inclined plane. The coefficient of friction between the surface and the block is $\mu$. At what angle of inclination $\theta$ of the plane to the horizontal will the block just start to slide down the plane?
In the given arrangement the maximum value of $F$ for which there is no relative motion between the blocks