Question
Download Solution PDFThe pressure inside a soap bubble of 50 mm diameter is 25 N/m2 above atmospheric pressure. The surface tension in soap film would be
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFConcept:
Surface tension on a liquid droplet (Spherical droplet of water): Pressure intensity inside the droplet:
\(p = \frac{{4\sigma }}{d}\)
Surface tension on a hollow bubble (Soap bubble): Pressure intensity inside the droplet:
\(p = \frac{{8\sigma }}{d}\)
where σ is the surface tension of the liquid.
Calculation:
\({\rm{\Delta }}P = \frac{{8\sigma}}{d}\)
\(\sigma = \frac{{\Delta P\times d}}{8 } =\frac{{25\times 0.05}}{8 }= 0.15625 \ N/m\)
Last updated on Jun 23, 2025
-> UPSC ESE result 2025 has been released. Candidates can download the ESE prelims result PDF from here.
-> UPSC ESE admit card 2025 for the prelims exam has been released.
-> The UPSC IES Prelims 2025 will be held on 8th June 2025.
-> The selection process includes a Prelims and a Mains Examination, followed by a Personality Test/Interview.
-> Candidates should attempt the UPSC IES mock tests to increase their efficiency. The UPSC IES previous year papers can be downloaded here.