I know that when two soap bubbles of different radii are connected by a tube then air will flow from the smaller bubble to the bigger bubble. This happens because the pressure inside the smaller bubble is greater than that inside the bigger bubble : the pressure difference between the outside and inside of any soap bubble is inversely proportional to its radius.
But I was wondering that what will happen if we connect two different spherical party balloons with a tube. Will the result be the same as with soap bubbles or will it be the opposite to that?
Logic tells me that the pressure inside the larger balloon will be greater than inside the smaller one, so air will flow from the bigger balloon to the smaller. My reason is that when I blow air from my mouth into a balloon, I find it more difficult as it gets bigger and bigger. This suggests that the bigger balloon must be applying more air pressure than the smaller one.
So what is the right answer? If it is same as with soap bubbles then what is the reason? Is there any formula for such cases which can give us relation between radius of balloon & pressure inside, just like bubbles?