Question

Why does speed of blood in arteries differ from speed of blood in capillaries

Answer 1

The keyword here is "area per volume" which is available in both cases. Besides capillaries are smaller than arteries they have in total more area as there are many vessels of then. The More the area/volum, the less the velocity

Answer 2

The difference arteries and Capillaries lies on their size

Capillaries have huge cross sectional area Than the arteries

The larger the size is, the smaller its velocity would be.

Which why the speed of blood in arteries would be faster compared to the one in Capillaries

hope this helps