Maurine: Oh no, I forgot my wallet. Could you lend me three dollars for some coffee?
Catherine: I would, but I’m completely broke! Sorry!

When you are broke, you have no money at all. If you knock a vase off of a table and it breaks, it is not broke; it is broken. (However, “broke” is still the past tense of “break”.) The gesture of pulling a pocket inside out shows that there is no money inside.