Determine the time in which the smaller block reaches the other end of the bigger block as shown in the figure. $(g = 10\ m s^{-2})$.

Block $A$ of mass $100 \ kg$ is kept above another block $B$ of mass $300 \ kg$. Block $A$ is tied to the wall $C$ with a horizontal string. The coefficient of friction between $A$ and $B$ is $0.35$ and that between $B$ and the horizontal surface is $0.5$. Find the horizontal force $P$ necessary to move the block $B$. (in $N$)

The coefficient of friction between blocks $A$ and $B$ is $\mu$. The minimum force $F$ with which $A$ must be pushed such that $B$ will not slip down is

Consider the system shown below. $A$ horizontal force $F$ is applied to a block $X$ of mass $8 \,kg$,such that the block $Y$ of mass $2 \,kg$ adjacent to it does not slip downwards under gravity. There is no friction between the horizontal plane and the base of the block $X$. The coefficient of friction between the surfaces of blocks $X$ and $Y$ is $0.5$. The minimum value of $F$ is ............ $N$ (take acceleration due to gravity to be $10 \,ms^{-2}$).

Three blocks $A$,$B$,and $C$ of equal mass $m$ are placed on a smooth surface as shown. The coefficient of friction between any two blocks $A$,$B$,and $C$ is $\mu$. The maximum value of mass $M$ of block $D$ such that blocks $A$,$B$,and $C$ move without slipping over each other is:

The maximum value of $F$ which can be applied on the system shown in the figure so that both blocks move together with the same acceleration is ..........