In figure, the coefficient of friction between the floor and the block $B$ is $0.2$ and  between blocks $A$ and $B$ is $0.3$. ........ $N$  is the maximum horizontal force $F$ can be  applied to the block $B$ so that both blocks move together .

To avoid slipping while walking on ice, one should take smaller steps because of the

A body of mass $2 \,kg$ is kept by pressing to a vertical wall by a force of $100\, N$. The coefficient of friction between wall and body is $0.3.$ Then the frictional force is equal to ........ $N$

A man pulls a block heavier than himself with a light horizontal rope. The coefficient of friction is the same between the man and the ground, and between the block and the ground

The frictional force acting on $1 \,kg$ block is .................. $N$

A wooden block of mass $M$ resting on a rough horizontal surface is pulled with a force $F$ at an angle $\phi $ with the horizontal. If $\mu $ is the coefficient of kinetic friction between the block and the surface, then acceleration of the block is