code: def head_orifice(Diam, RatioVCOrifice, FlowRate):
      
      #Checking input validity
      ut.check_range([Diam, ">0", "Diameter"], [FlowRate, ">0", "Flow rate"],
                     [RatioVCOrifice, "0-1", "VC orifice ratio"])
      return ((FlowRate
               / (RatioVCOrifice * area_circle(Diam).magnitude)
               )**2
              / (2*gravity.magnitude)
              )
docs: Return the head of the orifice.