A capillary-balance scan compares upward surface-tension support with the liquid column's weight across three rows, marking where the capillary height balance closes. The arithmetic is exact only for the stated surface tension, contact angle, density, radius, height, and rows in the ideal capillary-tube model. Real measurements add wetting/contact-angle variation, contamination, curvature departures, temperature, instrument calibration, finite precision, and measurement uncertainty.
Column height is scanned below, at, and above the capillary balance. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Column height is scanned through the balance point
The capillary pressure remains 20 Pa while the liquid column height is 1 over 2 m. That gives a column pressure of 10 Pa and accepted bit 0 because the row is below the balance.
Pc=20Pa,Pcol=10Pa,b=0
Column height is scanned through the balance point
The capillary pressure remains 20 Pa while the liquid column height is 1 m. That gives a column pressure of 20 Pa and accepted bit 1 because the row is at the balance.
Pc=20Pa,Pcol=20Pa,b=1
Column height is scanned through the balance point
The capillary pressure remains 20 Pa while the liquid column height is 3 over 2 m. That gives a column pressure of 30 Pa and accepted bit 0 because the row is above the balance.