Question

Find the difference of air pressure between the inside and outside of a soap bubble $5\,mm$ in diameter, if the surface tension is $ 1.6\,N{{m}^{-1}} $

• A. $ 2560\,N{{m}^{-2}} $
• B. $ 3720\,N{{m}^{-2}} $
• C. $ 1208\,N{{m}^{-2}} $
• D. $ 10132\,N{{m}^{-2}} $

Answer 1

Answer: (A)

$ P=\frac{4T}{R}=\frac{4\times 1.6}{2.5\times {{10}^{-3}}} $ $ =2560\,N/{{m}^{2}} $