Question about using the Wihelmy blade method

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The discussion focuses on the application of the Wilhelmy blade method to measure interfacial tension for a paracetamol compact submerged in water. Participants analyze various statements regarding surface tension and contact angles, questioning their accuracy based on provided measurements. The surface tension is debated as being 23 in/dyn, while the interfacial tension is suggested to be 58.6 mN/m. There is confusion regarding the calculation of contact angles, with two different values proposed: 19.15 mN/m and 32.15 mN/m. The conversation emphasizes the need for proper unit conversion and understanding of the method's equations.
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Homework Statement
the wihelmy blade method
Relevant Equations
COSθ= F/P* ƔLV
for the wihelmy blade method we want to measure the interfacial tension exerted on a paracetamol compact in the shape of a rectangular parallepiped perimeter submerged 0.12 m in water we measure a force of 0.21 mN for a contact angle of 88.29°

answer whether they are true or false

Surface tension is 23 in/dyn
la tension interfaciale entre la lame de paracetamol et l'eau est 58,6mN/m
the contact angle between the paracetamol blade and the water 19.15mN/m
the contact angle between the paracetamol blade and the water is 32.15m/mNI think that the interfacial tension is 58.6mN/m because of question c I do not understand how to calculate the contact angle between the paracetamol sheet and the water
 

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havenly said:
Homework Statement:: the wihelmy blade method
Relevant Equations:: COSθ= F/P* ƔLV

answer whether they are true or false

Surface tension is 23 in/dyn
la tension interfaciale entre la lame de paracetamol et l'eau est 58,6mN/m
the contact angle between the paracetamol blade and the water 19.15mN/m
the contact angle between the paracetamol blade and the water is 32.15m/mN
It seems to be a simple problem of converting 23 inch/dyne to meter/milliNewton.

Please, see:
https://en.wikipedia.org/wiki/Wilhelmy_plate

https://www.researchgate.net/profile/Virginija_Jankauskaite/publication/285514136/figure/fig1/AS:670019541295122@1536756515903/Schematic-representation-of-Wilhelmy-plate-method.png
 
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