$A$ dynamometer $D$ is attached to two blocks of masses $6 \, kg$ and $4 \, kg$ as shown in the figure. The reading of the dynamometer is ............ $N$.

Two bodies $A$ and $B$ of masses $10\, kg$ and $15\, kg$ respectively,kept on a smooth horizontal surface,are tied to the ends of a light string. If $T$ represents the tension in the string when a horizontal force $F = 500\, N$ is applied to $A$ (as shown in figure $I$) and $T'$ is the tension when it is applied to $B$ (figure $II$),then which of the following is true?

$A$ system of $10$ balls,each of mass $m = 2 \; kg$,is connected via a massless and unstretchable string. The system is allowed to slip over the edge of a smooth table as shown in the figure. Find the tension $T$ in the string between the $7^{th}$ and $8^{th}$ ball when the $6^{th}$ ball just leaves the table. (in $; N$)

Three blocks of masses $4\, kg, 8\, kg$ and $24\, kg$ are connected to each other with light strings and placed on a smooth horizontal floor as shown in the figure. If the system moves with an acceleration of $2\, m/s^2$,the applied force $F$ is ............ $N$.

$A$ body of mass $8\,kg$ is hanging from another body of mass $12\,kg$. The combination is being pulled upwards by a string with an acceleration of $2.2\,m/s^2$. The tensions $T_1$ (in the top string) and $T_2$ (in the string between the two masses) will be respectively: (use $g = 9.8\,m/s^2$)

An elevator of mass $500 \,kg$ is ascending upwards with a constant acceleration $a=2 \,m/s^2$. What is the work done by the tension in the elevator cable during its climb by $12 \,m$ (in $\,kJ$)? (Take $g=10 \,m/s^2$)