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was removed from the list of probable causes. Focus shifted to the potentiometer screws
and the pressure sensors for root cause analysis.
By a series of experiments, it was determined that the voltage readings changed
dynamically even with no liquid inflow to the tank. Figure 5.2 depicts this phenomenon.
Figure 5-2 Dynamic Change in Pressure Sensor Reading for No Pump Voltage.
Eventually, formation of air pockets was observed in the pressure sensors. These
air pockets would reduce the tank voltage reading because they are less dense than water
and would absorb some of the water head pressure as shown in Figure 5-2. Proceeding
with the assumption that these air pockets might be the root cause for the incoherent
readings, a procedure for removal of air pockets was developed. The teaching assistant
performed the procedure for removing the air pockets before calibrating the sensors.
Then a series of 10 trials for both experiment 2 and experiment 3 was performed to make
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