First thing in the morning I just must have a cup of tea, well, mug actually.
Like many others, I whack a Typhoo tea bag (other tea bags are available) in a mug and pour on boiling water. The tea bag is full of perforations to 'let flavour flood out' (other slogans are available).
Now here's the question, if my tea bag is full of perforations, why does it blow up like a balloon? Even when I push it under the water, it just bobs back to the surface like a, like a........ floaty thing. Why doesn't the air just escape through those perforations and the tea bag sink?
Please write your answers on the back of a tea bag.
To assist you in finding the back of a tea bag, here is a typical tea bag. Front of tea bag Back of tea bag