A jet of air moving with a speed of $50\;m/s$ with diameter $10\;mm$ strikes a disc kept vertical what is the force exerted by the air jet on the disc. (density of air $1.03\;kg/m^3)$

Question

$\begin{array}{1 1} 1\;N \\ 2\;N \\ 0.1\;N \\ 0.2\;N \end{array} $