Answer
(a) $19KPa$
(b) $1.96KN$
Work Step by Step
(a) We can find the pressure difference as
$P_{in}-P_{out}=\frac{1}{2}\rho(v_{out}^2-v_{in}^2)$
We plug in the known values to obtain:
$P_{in}-P_{out}=\frac{1}{2}(1.29Kg/m^3)((170)^2-(0)^2)=19KPa$
(b) We know that
$\Delta P=\frac{F}{A}$
This can be rearranged as:
$F=\Delta PA$
We plug in the known values to obtain:
$F=(18.6\times 10^3Pa)(0.25m)(0.42m)=1.96KN$
