Water at 60˚f flows through a nozzle that contracts from a diameter of 3 in. to 0.5 in. the pressure at section 1 is 2500 psfg, and atmospheric pressure prevails at the exit of the jet. calculate (a) the speed of the flow at the nozzle exit and (b) the force required to hold the nozzle stationary. neglect weight.

Let's start by getting the expressions for the speed that allow us to get the equations correctly,

Then,

Replacing then

We then proceed to obtain the speed, from the previously given relationship,

So,

Where is the pressure in each section,

As section 2 is open, then and

a) The velocity at section 2 would be,

b) The discharge Q would be,

The force then is,

Solving,

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂