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

To find the radius of curvature of the common surface when two soap bubbles of radii a and b (where b > a) coalesce, we can follow these steps:

1. Start by understanding the concept of coalescence. When two soap bubbles merge, they form a common surface between them.

2. The radius of curvature of a surface is a measure of how sharply it curves at a particular point. In this case, we want to find the radius of curvature of the common surface formed when the soap bubbles coalesce.

3. The radius of curvature can be calculated using the formula:

   Radius of Curvature = (a * b) / (a + b)

   Here, a and b are the radii of the two soap bubbles.

4. Substitute the given values of a and b into the formula. Make sure to use the correct values for a and b, where b is greater than a.

5. Calculate the result using the formula. This will give you the radius of curvature of the common surface.

By following these steps, you can find the radius of curvature of the common surface when two soap bubbles of radii a and b (where b > a) coalesce.