A uniform force of \((3\hat{i}+\hat{j})\) newton acts on a particle of mass 2 kg. Hence the particle is displaced from position \((2\hat{i}+\hat{k})\) meter to position \((4\hat{i}+3\hat{j}+\hat{k})\) meter. The work done by the force on the particle is : 

9 J

$\vec{F} = (3\hat{i}+\hat{j})$

$R_i = 2\hat{i}+\hat{k}$ 

$R_f = 4\hat{i}+3\hat{j}+\hat{k}$

Displacement $\vec{S} = \vec{R_f}-\vec{R_i} = 2\hat{i}+3\hat{j}$

\( W = \vec{F}.\vec{S}\)

\( W = 9 J \)