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Question
State Stoke’s law and give two factors affecting angle of contact.
Solution
Statement: The viscous force acting on a small sphere falling through a medium is directly proportional to the radius (r) of the sphere, its velocity (v) through fluid, and coefficient of viscosity (η) of the fluid.
Two factors affecting the angle of contact:
- The nature of the liquid and the solid in contact.
- Impurities present in the liquid change the angle of contact.
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