A raindrop with radius R = 0.2 mm falls from a cloud at a height h = 2000 m above the ground. Assume that the drop is spherical throughout its fall and the force of buoyancy may be neglected, then the terminal speed attained by the raindrop is:

$$\begin{gathered} [\mathrm{Density} \mathrm{of} \mathrm{water} {\mathrm{f}}_{\mathrm{w}}=1000 {\mathrm{kgm}}^{-3} \mathrm{and} \mathrm{Density} \mathrm{of} \mathrm{air} {\mathrm{f}}_{\mathrm{a}}=1.2 {\mathrm{kgm}}^{-3}, \\ \mathrm{g}=10\mathrm{m}/{\mathrm{s}}^2. \mathrm{Coefficient} \mathrm{of} \mathrm{viscosity} \mathrm{of} \mathrm{air}=1.8\times {10}^{-5}{\mathrm{Nsm}}^{-2}] \end{gathered}$$