In the diagram shown, the normal reaction force between $2\,kg$ and $1\,kg$ is (Consider the surface, to be smooth)$.........N$ (Given $g =10\,ms ^{-2}$)

Three blocks $A, B$ and $C $ weighing $1, 8$ and $27\, kg$ respectively are connected as shown in the figure with an inextensible string and are moving on a smooth surface. ${T_3}$ is equal to $36\, N$. Then ${T_2}$ is ........ $N$

A wedge of height $H$ (fixed) and inclination $\alpha $ (variable) is moving on a smooth horizontal surface with constant acceleration $g\ m/s^2$ . A small block is placed at bottom of incline as shown in figure, slips on the smooth surface of incline . Choose $CORRECT$ statement about time taken by block to reach the top of incline

Three masses of $16, 8$ and $4\,kg$ are placed in contact as shown in figure. If a force of $140\,N$ is applied on $4\,kg$ mass, then the force on $16\,kg$ will be  ............ $ N$

Two masses of $5\, kg$ and $3\, kg$ are suspended with the help of massless inextensible strings as shown in figure. The whole system is going upwards with an acceleration of $2\, ms^{-2}$. The tensions $T_1$ and $T_2$ are respectively (Take $g = 10\, ms^{-2}$)

A block $B$ is placed on block $A$. The mass of block $B$ is less than the mass of block $A$. Friction exists between the blocks, whereas the ground on which the block $A$ is placed is taken to be smooth. $A$ horizontal force $F$, increasing linearly with time begins to act on $B$. The acceleration ${a_A}$ and ${a_B}$ of blocks $A$ and $B$ respectively are plotted against $t$. The correctly plotted graph is