How is flow measured in square root?

Flow varies directly as the square root of pressure. Thus, F=K of square root of applied pressure. Since this flow varies as the square root of differential pressure. The pressure pen does not directly indicate flow. Thus flow can be determined by taking the square root of the pen. Assume the pen reads50% of the chart. So, flow can be calculated using the pen measure in the chart.

F=10*Sq.root Differential Pressure

Q=((p)^0.5)  ×const