An air bubble of radius 4.5 cm initially at a depth of 12 m below the water surface rises to the surface. If the atmospheric pressure is equal to 10.34 m of water, the radius of the bubble just before it reaches the water surface is
The correct answer is: D
Explanation
\(r_1\) = 4.5cm , \( P_1\) =is the total pressure on the bubble at a depth of 12m from the surface.
\(P_1\) = 12 + 10.34 =22.34m
\(V_1\) = \(\frac{4}{3}\)ΟΓ \(r^3_1\)
= \(\frac{4}{3}Γ ΟΓ{4.5^3cm^3}\)
\(P_2\) = 10.34m
\(V_2\) = \(\frac{4}{3} {Ο}{r^3_2}\)
from boyles law:
\(P_1V_1\) = \(P_2V_2\)
β 22.34Γ \(\frac{4}{3}Γ ΟΓ{4.5^3}\) = 10.34 Γ \(\frac{4}{3}ΓΟΓ{r^3_2}\)
β 22.34 Γ \(4.5^3\) = 10.34 Γ \(r^3_2\)
β \(r^3_2 = \sqrt[3]{196.88}\)
β \(r_2\) = 5.82cm
There is an explanation video available .