1 99:59:59,999 --> 99:59:59,999 so lets say you're walking down the street 2 99:59:59,999 --> 99:59:59,999 and im going to draw you here and you decide to do a little experiment. 3 99:59:59,999 --> 99:59:59,999 you take a deep breath as you're walking and you decide to blow out a cardboard tube 4 99:59:59,999 --> 99:59:59,999 something like that 5 99:59:59,999 --> 99:59:59,999 lets say its like a toilet paper roll 6 99:59:59,999 --> 99:59:59,999 and so you blow out through it 7 99:59:59,999 --> 99:59:59,999 and here in this toilet paper roll 8 99:59:59,999 --> 99:59:59,999 the length is, lets call, l and the radius and i'll call it r 9 99:59:59,999 --> 99:59:59,999 and you know a toilet paper roll is, lets say about 2 cm 10 99:59:59,999 --> 99:59:59,999 radius. That may not be exactly right but lets just assume that. 11 99:59:59,999 --> 99:59:59,999 And you do this and you find that it is so easy to do. 12 99:59:59,999 --> 99:59:59,999 Very easy to take one breath of air and blow it out an blow it out of a cardboard tube