Du Noüy ring method
![A du Noüy ring tensiometer. The arrow on the left points to the ring itself.](/Images/godic/202501/10/Du_Nouy_tensiometer5855.jpg")
![Close up of the ring drawn out of the liquid.](/Images/godic/202501/10/Ptirgyuru5855.jpg")
The du Noüy ring method is one technique by which the surface tension of a liquid can be measured. The method involves slowly lifting a ring, often made of platinum, from the surface of a liquid. The force, ![F](/Images/godic/202501/10/800618943025315f869e4e1f094710125855.png")
, required to raise the ring from the liquid's surface is measured and related to the liquid's surface tension, ![\gamma](/Images/godic/202501/10/334de1ea38b615839e4ee6b65ee1b1035855.png")
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