Question

Describe capillary rise method to determine surface tension of liquid. Derive the necessary formula.

Answer 1

Pressure =densitygh

So densitygh =2T/R

Then H=2T/densityRg

Where H stands foto capallary rise

Answer 2

The capillary rise method is a test that is used to detect a liquid's surface tension or contact angle with soil or pipe material.

• The increase in a liquid above zero pressure level induced by net upward force created by the attraction of water molecules to a solid surface is known as capillary rise.
• The liquid level in the capillary tube lowers when the adhesion forces between the liquid and the capillary wall are weaker than the cohesive forces between the liquid molecules, causing the meniscus to become convex.

• Necessary formula for this,

         Tension of liquid=density of the liquid× g× height(H)×Radius(r)

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