The level of blood in bottle used to give blood to a patient is 1.3 m high above the needle which is 3 cm in length and has internal diameter of 0.36 mm. If 4.5 cm^3 of blood is passing through the needle per minute, calculate the viscosity of blood. The density of blood is 1020 kg/m^3.
Ignore fall in level of blood in the bottle.
For a fluid flowing through a cylindrical pipe we have Poiseuilli equation which gives us the pressure drop.
L = 3 c m = 0 . 03 m
ϕ = 4 . 5 c m 3 / m i n = 7 . 5 × 10 - 8 m / s e c
∆ P = ρgh = 1020 × 9 . 8 × 1 . 3 = 12994 . 8 Nm - 2