Final answer:
The significance of two radii of curvature in the formula for excess pressure due to surface tension indicates a non-spherical liquid surface. This formula is essential for calculating the gauge pressure inside liquid droplets or bubbles depending on the surface tension and shape.
Step-by-step explanation:
The formula 2T (1/R₁ + 1/R₂) represents the excess pressure inside a liquid with two radii of curvature due to surface tension. Surface tension is essentially the energy required to stretch or increase the surface area of a liquid, and it is the cause behind the formation of droplets and bubbles. The presence of two radii in the formula implies a non-spherical shape, such as an ellipsoid. For a spherical bubble, these radii are equal, and the formula simplifies. The gauge pressure P inside can then be calculated using known values of surface tension (T) and the radii (R₁ and R₂). It's noteworthy that surface tension varies greatly between different liquids due to the nature of intermolecular forces.