In aorta, U<SUB>AA</SUB> is ~20 cm/sec.
In capillaries, U<SUB>cap</SUB> is ~ 0.05 cm/sec.
This is 400:1 range!
» The velocity ↓ due to combined effects of an <i>↑ in number (n) of parallel vessels from aorta to capillaries</i> and the <i>★ large cross sectional area of the capillary network</i>.
★ Main reason (REMEMBER: <span style="color: #ff0000;">U = Q/A</span>)