Surface Tension Problems And Solutions Pdf Apr 2026

: Surface area change: (A_2 - A_1 = 4\pi (R_2^2 - R_1^2)) Bubble has 2 surfaces → multiply by 2. [ \Delta A = 2 \times 4\pi (0.10^2 - 0.05^2) = 8\pi (0.01 - 0.0025) ] [ \Delta A = 8\pi (0.0075) = 0.1885 \ \text{m}^2 ] Work = (\gamma \times \Delta A = 0.03 \times 0.1885 \approx 0.00566 \ \text{J}) Answer : (5.66 \times 10^{-3} \ \text{J}) If you want, I can format these into a clean PDF-ready LaTeX or Markdown document for you to compile or print. Just let me know.

: Water contacts the ring along inner and outer circumference. [ L = 2 \times (2\pi R) = 4\pi R ] [ F = \gamma \cdot L = 0.072 \times 4\pi \times 0.05 ] [ F = 0.072 \times 0.6283 \approx 0.0452 \ \text{N} ] Answer : 0.045 N (approx.) Problem 2: Excess pressure in a soap bubble Problem : A soap bubble of radius 2 cm has surface tension 0.025 N/m. Find excess pressure inside. surface tension problems and solutions pdf

: [ h = \frac{2\gamma \cos\theta}{\rho g r} ] [ 0.03 = \frac{2 \times 0.072 \times \cos\theta}{1000 \times 9.8 \times 0.0005} ] [ 0.03 = \frac{0.144 \cos\theta}{4.9} ] [ 0.144 \cos\theta = 0.147 ] [ \cos\theta \approx 1.02 \ \text{(impossible → means } \theta \approx 0^\circ\text{)} ] Answer : (\theta \approx 0^\circ) (water wets glass perfectly) Problem 4: Two bubbles in contact Problem : Two soap bubbles of radii 3 cm and 4 cm coalesce. Find radius of curvature of common interface. : Surface area change: (A_2 - A_1 =

I cannot directly provide a PDF file, but I can give you a that you can copy into a document and save as a PDF yourself. : Water contacts the ring along inner and

: [ \Delta P = \frac{4\gamma}{R} = \frac{4 \times 0.025}{0.02} = \frac{0.1}{0.02} = 5 \ \text{Pa} ] Answer : 5 Pa Problem 3: Capillary rise Problem : Water rises to 3 cm in a capillary tube of radius 0.5 mm. If surface tension of water is 0.072 N/m, density = 1000 kg/m³, find contact angle. Take (g = 9.8 \ \text{m/s}^2).