When two soap bubbles of radii a and b (b &gt; a) coalesce, the radius of curvature of common surface is: &lt;!-- [if !supportLineBreakNewLine]--&gt; &lt;!--[endif]--&gt; &lt;!--[endif]--&gt;

ab / (b - a)

ab / (a + b)

(b - a) / ab

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Surface Tension Physics Mechanical Properties of Fluids Physics Class 11th

When two soap bubbles of radii a and b (b > a) coalesce, the radius of curvature of common surface is:

Option 1 -

ab / (a + b)

Option 2 -

ab / (b - a)

Option 3 -

(b - a) / ab

Option 4 -

(a + b) / ab

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1 Answer

Answered by

Vishal Baghel | Contributor-Level 10

a month ago

Correct Option - 2

Detailed Solution:

P? - P? = 4T/a

P? - P? = 4T/b

P? - P? = 4T (1/a - 1/b)

Also, P? - P? = 4T/r

4T/r = 4T (1/a - 1/b)

1/r = (b-a)/ab

r = ab / (b-a)

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