The Plate Method According To Wilhelmy - kruss K11 MK3 User Manual

Measuring principles
Correction
For ring measurements the measured values must be corrected since the results are
otherwise falsified by two effects:
• The weight of the uplifted amount of liquid underneath the ring increases the value
of the force detected by the force sensor.
• The force maximum is not reached at the same time on the inner and the outer side
of the ring.
With K11, the correction is performed automatically with the correction method
selected in the ring method menu. The method according to Harkins & Jordan can be
used in most cases.
15.1.2

The plate method according to Wilhelmy

In the plate method the liquid is raised until the contact between the surface or
interface and the plate is registered. On contact with the surface or interface, the
surface or interfacial tension acts on the plate. This vertical force is detected by a force
sensor; the surface or interfacial tension is calculated from the measured force and the
wetted length of the plate.
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