Question

In the system shown in figure, the acceleration of 1kg mass is

• A. $\frac{g}{4}$ downwards
• B. $\frac{g}{2}$ downwards
• C. $\frac{g}{2}$ upwards
• D. $\frac{g}{4}$ upwards

Answer 1

The correct option is C

$\frac{g}{2}$ upwards

$4g-2T=4a\dots \left(i\right)$

The equation of motion or 1 kg block is

$T-1g=1\times 2a\dots \left(ii\right)$

or $2T-2g=4a\dots \left(iii\right)$

Adding (i) and (iii), we get

$2g=8a$ or $a=\frac{g}{4}$

$\therefore$ Acceleration of 1 kg block = $2a=\frac{g}{2}$ upwards