A perfect smooth sphere $A$ of mass $2\  kg$ is in contact with a rectangular block $B$ of mass $4\  kg$ and vertical wall as shown in the figure. All surfaces are smooth. Find normal reaction by vertical wall on sphere $A$  .......... $N$

Two blocks are connected by a string as shown in the diagram. The upper block is hung by another string. A force $F$ applied on the upper string produces an acceleration of $2\,m/{s^2}$ in the upward direction in both the blocks. If $T$ and $T'$ be the tensions in the two parts of the string, then $T$ and $T'$

A block of mass $200\, g$ is kept stationary on a smooth inclined plane by applying a minimum horizontal force $F =\sqrt{ x }N$ as shown in figure. The value of $x =.....$

A constant force $F$ is applied in horizontal direction as shown in figure. Contact force between $M$ and $m$ is $N$ and between $m$ and $M'$ is $N'$ then

What force should be applied on the wedge so that block over it does not move? (All surfaces are smooth)

Three blocks are connected as shown in figure on a horizontal frictionless table. If $m_1 =  1kg, m_2 = 8kg, m_3 = 27\, kg$ and $T_3 = 36N, T_2$ will be ............ $N$