$A$ block $A$ of mass $100\, kg$ rests on another block $B$ of mass $200\, kg$ and is tied to a wall as shown in the figure. The coefficient of friction between $A$ and $B$ is $0.2$ and that between $B$ and the ground is $0.3$. The minimum force $F$ required to move the block $B$ is........ $N$. $(g = 10\, m/s^2)$

$A$ block of mass $1\, kg$ lies on a horizontal surface in a truck. The coefficient of static friction between the block and the surface is $0.6$. If the acceleration of the truck is $5\, m/s^2$,the frictional force acting on the block is ........ $N$.

$A$ system of two blocks of masses $m = 2 \; kg$ and $M = 8 \; kg$ is placed on a smooth table as shown in the figure. The coefficient of static friction between the two blocks is $0.5$. The maximum horizontal force $F$ that can be applied to the block of mass $M$ so that the blocks move together will be $\dots \; N$.

Block $A$ of mass $30\, kg$ is resting on a frictionless floor. Another block $B$ of mass $5\, kg$ is resting on it as shown in the figure. The coefficient of static friction between the blocks is $0.4$ while kinetic friction is $0.3$. If a horizontal force of $175\, N$ is applied to block $B$,then the acceleration of block $A$ will be ........ $m/s^2$ $(g = 10\, m/s^2)$.

What is the maximum force $F$ that can be applied on block $m_1$,so that both $m_1$ and $m_2$ will move together? There is no friction between $m_1$ and the horizontal table. The coefficient of friction between $m_1$ and $m_2$ is $\mu$.

The coefficient of friction between two blocks is $0.2$,and the coefficient of friction between block $B$ and the surface is $0.5$. If a force of $25 \ N$ is applied to block $B$ (mass $A = 2 \ kg$,mass $B = 8 \ kg$),what is the magnitude of the frictional force between the two blocks in $N$?