Question

In the arrangement shown in figure. The strings are light and inextensible. The surface over which blocks are placed is smooth. Find the tension in each string.

Answer 1

Free body diagram (showing the forces in x-direction only) of $4kg$ block and $1kg$ block are shown in the figure.
Using $a=\Sigma F_x=m{a}_x$
For $1kg$ block, $F-T_1=\left(1\right)\left(a\right)$
or $14-T_1=\left(1\right)\left(2\right)=2$
$\therefore T_1=14-2=12N$
For $4kg$ block, $T_2=\left(4\right)\left(a\right)$
$\therefore T_2=\left(4\right)\left(2\right)=8N$