A 2.16 N force is applied to the plunger of a hypodermic needle. If the diameter of the plunger is 1.19 cm and that of the needle 0.199 mm, by what force does the fluid leave the needle?
What force on the plunger would be required to push fluid into a vein where the measure pressure is 18.0 mm-Hg? Answer for the instant just before the fluid starts to move.