$A$ mass is hanging on a spring balance which is kept in a lift. The lift ascends with an acceleration. The spring balance will show in its readings:

$A$ wooden block of mass $5 \, kg$ rests on a soft horizontal floor. When an iron cylinder of mass $25 \, kg$ is placed on top of the block, the floor yields and the block and the cylinder together move down with an acceleration of $0.1 \, m/s^2$. The action force of the system on the floor is equal to: (in $N$)

Find the force $F$ required on the cart so that the $2 \ kg$ and $1 \ kg$ blocks remain stationary relative to the cart.

$A$ box of mass $m \, kg$ is placed on the rear side of an open truck accelerating at $4 \, m/s^2$. The coefficient of friction between the box and the surface below it is $0.4$. The net acceleration of the box with respect to the truck is zero. The value of $m$ is :- $[g = 10 \, m/s^2]$

$A$ block of mass $m$ is in contact with the cart $C$ as shown in the figure. The coefficient of static friction between the block and the cart is $\mu$. The acceleration $\alpha$ of the cart that will prevent the block from falling satisfies:

In the given arrangement,all surfaces are smooth. What acceleration $a$ should be given to the system (block $M$) so that the block $m_2$ does not slide down?