Four blocks are connected as shown in the fig. on a horizontal frictionless surface of $m_1 = m_2 = m_3 = m_4$ then $T_3/T_4$ will be

A block of mass $m$ slides down on a wedge of mass $M$ as shown in figure. Let $\vec a_1$ be the acceleration of the wedge and $\vec a_2$  the acceleration of block w.r.t. ground. $N_1$ is the normal reaction between block and wedge and $N_2$ the normal reaction between wedge and ground. Friction is absent everywhere. Select the incorrect alternative

Two blocks of masses $5\, kg$ and $4\, kg$ are in contact with each other on a frictionless table. When a horizontal force of $9\, N$ is applied to the block of mass $5\, kg$ , then the value of the force of contact between the two blocks is ........ $N$

A frictionless cart $A$ of mass $100\  kg$ carries other two frictionless carts $B$ and $C$ having masses $8\  kg$ and $4\  kg$ respectively connected by a string passing over a pulley as shown in the figure. What horizontal force $F$ must be applied on the cart so that smaller cart do not move relative to  it .......... $N$

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 $C,$ of masses $4\, kg, \,2 \,kg$ and $1\, kg$ respectively, are in contact on a frictionless surface, as shown. If a force of $14\, N$ is applied on the $4 \,kg$ block, then the contact force between $A$ and $B$ is  .......... $N$