Here are two common demonstrations of Bernoulli effects:
(a) If you hold a narrow strip of paper in front of your mouth and blow over the top surface, the strip will rise (Fig. 9.33a). (Try it.) Why?

(b) A plastic egg is sup-ported vertically by a stream of air from a tube (Fig. 9.33b). The egg will not move away from the mid-stream position. Why not?