A pipeline with variable cross-section contains water with specific weight
$${10^4}\,\,N/{m^3}.$$ The flow conditions at two points $$1$$ and $$2$$ on the axis of the pipe are:
$$\eqalign{ & {P_1} = 3\,\,bar,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{V_1} = 10\,\,m/s \cr & {P_2} = 1\,\,bar,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{V_2} = 20\,\,m/s \cr} $$

Consider frictional losses to be negligible. For no-flow condition between points $$1$$ and $$2$$ (as shown in Figure), if the height $${z_1}$$ from the datum is $$1$$ $$m,$$ then the height $${z_2}$$ (in $$m$$) is _____________ $$\left( {g = 9.81\,\,m/{s^2}} \right)$$

In a vertical piston-cylinder arrangement the force applied to the piston, pushes water through a nozzle as shown in the figure. The water flows out from the nozzle, and reaches the top of its trajectory. The kinetic and pressure energies at points $$(1), (2)$$ and $$(3),$$ respectively, are