$A$ mass of $1 \ kg$ is suspended by means of a thread. The system is
$(i)$ lifted up with an acceleration of $4.9 \ ms^{-2}$
(ii) lowered with an acceleration of $4.9 \ ms^{-2}$.
The ratio of tension in the first and second case is

$A$ small block of mass $m$ is placed on a wedge of mass $M$ as shown,which is initially at rest. All the surfaces are frictionless. The spring attached to the other end of the wedge has a force constant $k$. If $a'$ is the acceleration of $m$ relative to the wedge as it starts coming down and $A$ is the acceleration acquired by the wedge as the block starts coming down,then the maximum retardation of $M$ is:

For the given figure,what will be the contact force applied by the $6 \ kg$ block on the $4 \ kg$ block? ............ $N$

$A$ block of mass $18.5 \ kg$ kept on a smooth horizontal surface is pulled by a rope of $3 \ m$ length by a horizontal force of $40 \ N$ applied to the other end of the rope. If the linear density of the rope is $0.5 \ kg \ m^{-1}$ and initially the block is at rest,the time in which the block moves a distance of $9 \ m$ is: (in $s$)

$A$ block of mass $M$ on a horizontal smooth surface is pulled by a load of mass $M/2$ by means of a rope $AB$ and string $BC$ as shown in the figure. The length and mass of the rope $AB$ are $L$ and $M/2$ respectively. As the block is pulled from $AB = L$ to $AB = 0$,its acceleration changes from:

$A$ rope of length $10 \, m$ and linear density $0.5 \, kg/m$ is lying lengthwise on a smooth horizontal floor. It is pulled by a force of $25 \, N$. The tension in the rope at a point $8 \, m$ away from the point of application is ....... $N$