$\mathrm{Colour} \mathrm{code} \mathrm{of} \mathrm{given} \mathrm{colours} \mathrm{is} \mathrm{as} \mathrm{follows}$

Green $\to 5,$ Black $\to 0$, Red $\to {10}^2$, Silver $\to 10\%$ tolerance
$\therefore R=50\times {10}^2 \mathrm{\Omega }$
$$\begin{gathered} \mathrm{Electrical} \mathrm{power}, \mathrm{P}={\mathrm{I}}^2\mathrm{R} \\ \Rightarrow {\mathrm{I}}^2=\frac{\mathrm{P}}{\mathrm{R}} \end{gathered}$$
$$\begin{gathered} \mathrm{where}, \\ \mathrm{I}-\mathrm{electric} \mathrm{current}, \\ \mathrm{R}-\mathrm{electric} \mathrm{resistance} \end{gathered}$$
${\mathrm{I}}^2=\frac{2}{50\times {10}^2}=4\times {10}^{-4} \mathrm{A}$
$\mathrm{I}=2\times {10}^{-2}\mathrm{A}=20\mathrm{mA}$