Rankers Physics

Surface Tension and Viscosity: Practice Problem & Solution

A liquid does not wet the solid surface if angle of contact is: (2020-Covid)
Equal to $60^\circ$
Greater than $90^\circ$
Zero
Equal to $45^\circ$

Solution Explained:

To solve this problem, we apply the core principles of Surface Tension and Viscosity. Understanding the underlying formula is key to arriving at the correct answer below:

For a liquid to not wet a solid surface, it must form an obtuse angle of contact. Therefore, the angle of contact must be greater than $90^\circ$.

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