System show in figure is released from rest.  Friction is absent and string is massless.  In time  $t=0.3s.$
 

	Column-I		Column-II
A	Work done by gravity on 2 kg block	P	$-1.5J$
B	Work done by gravity on 1 kg block	Q	$2J$
C	Work done by string on 2 kg block	R	$3J$
D	Work done by string on 1 kg block	S	$-2J$

On 1 kg

$\begin{array}{l}\text{ On }1 \mathrm{kg}\\ {\mathrm{m}}_2 \mathrm{g}-\mathrm{T}={\mathrm{m}}_2\mathrm{a}\\ \mathrm{On} 2 \mathrm{kg}\\ {\mathrm{m}}_2 \mathrm{g}-\mathrm{T}={\mathrm{m}}_2\mathrm{a}\\ \mathrm{a}=\frac{\left({\mathrm{m}}_2\mathrm{g}-{\mathrm{m}}_1\mathrm{g}\right)}{\left({\mathrm{m}}_1+{\mathrm{m}}_2\right)}=\frac{\mathrm{g}}{3}\\ \mathrm{T}=\frac{4 \mathrm{g}}{3}\\ \text{ Displacement }=\frac{{\mathrm{at}}^2}{2}=\mathrm{g}\times \frac{0.09}{3}=0.15 \mathrm{m}\end{array}$

A) work done by gravity on 2 kg is

$\text{ F.S }=2\times \mathrm{g}\times 0.15=3 \mathrm{J}$

B) Workdone by gravity on 1 kg is

$\mathrm{F}.\mathrm{S}=-1\times \mathrm{g}\times 0.15=-1.5 \mathrm{J}$

C) Work done by string on 2 kg is 

$\mathrm{T}.\mathrm{S}=-\mathrm{T}\times 0.15=4 \mathrm{g}\times \frac{0.15}{3}=-2 \mathrm{J}$

D) Workdone by string on 1 kg is

$\mathrm{T}.\mathrm{S}=\mathrm{T}\times 0.15=4 \mathrm{g}\times \frac{0.15}{3}=2 \mathrm{J}$