Two blocks A and B of masses m & 2m respectively are held at rest such that the spring is in natural length. Find out the accelerations of both the blocks just after release

$2\text{mg}-T=2{\text{ma}}_{\text{1}}\to \left(1\right)$

Force equation at m

$\text{mg}-\text{k}x={\text{ma}}_{\text{2}}\to \left(\text{2}\right)$

Equations have been written considering${\text{a}}_{\text{1}}\text{and}{\text{a}}_{\text{2}}$ downwards

When the blocks are released, $x=0,\text{k}x=0$

${\text{a}}_2=\text{g}$

$\text{T}=\text{k}x=\text{0}$

$\text{2mg}-\text{T}={\text{2ma}}_1$

${\text{a}}_{\text{1}}=\text{g}$