$A$ force of $mg$ is applied to block $B$ to keep the system in equilibrium. Find the value of $T_1$.

When a body moves with some friction on a surface,

$A$ body of mass $6 \,kg$ is moving with a uniform velocity $4 \,m/s$. Its velocity changes to $6 \,m/s$ when a force of $12 \,N$ acts on it. Then its displacement is (in $\,m$)

Two blocks $A$ and $B$ of masses $5 \ kg$ and $10 \ kg$ respectively are placed as shown in the figure. The coefficient of friction between all the surfaces is $0.2$. $A$ force $F$ is applied on block $A$ at an angle of $30^{\circ}$ with the horizontal. If the system moves with constant acceleration,find the acceleration of block $B$. (Assume $g = 10 \ m/s^2$ and $F = 100 \ N$) (in $m/s^2$)

For the given system,find the tension $T_2$ in the upper string.

$A$ block of mass $25 \ kg$ is pulled along a horizontal surface by a force at an angle $45^{\circ}$ with the horizontal. The friction coefficient between the block and the surface is $0.25$. The block travels at a uniform velocity. The work done by the applied force during a displacement of $5 \ m$ of the block is (in $J$)