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

$T_1$ and $T_2$ in the given figure are

A block '$A$' takes $2\,s$ to slide down a frictionless incline of $30^{\circ}$ and length ' $l$ ', kept inside a lift going up with uniform velocity ' $v$ '. If the incline is changed to $45^{\circ}$, the time taken by the block, to slide down the incline, will be approximately $........\,s$

In the given arrangement all surfaces are smooth. What acceleration should be given to the system, for which the block $m_2$ doesn't slide down?

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

Figure shows three blocks in contact and kept on a smooth horizontal surface. What is ratio of force exerted by block $A$ on $B$ to that of $B$ on $C$