Surface Tension & Viscosity

Surface energy, capillary rise; Newton's viscosity law.

Concept

Surface Tension & Viscosity is a foundational idea in this chapter. The defining relationship is:

$h = 2T\cos\theta/(\rho gR)$

Terminal velocity in viscous fluid: v_t = 2r²(ρ-σ)g/(9η).

Worked Application

Apply the formula to a typical problem from your textbook. Identify the knowns, plug into the equation, and check that the units work out. Always sanity-check the magnitude before accepting an answer.

Common Confusions

• Confusing the variables in the formula — re-read the symbol definitions in the chapter.
• Forgetting unit conversions (cm vs m, g vs kg).
• Ignoring sign conventions where direction matters.

Key Takeaways

• Master the formula $h = 2T\cos\theta/(\rho gR)$ and one canonical example.
• See the chapter index for full derivations, traps and exam-grade problems.