# Question: 2 assume a human can develop 3000 pa of vacuum...

###### Question details

2) Assume a human can develop 3000 Pa of vacuum pressure (suction) using their lungs. Would it be possible to drink a smoothie of density 1200 kg/m3 and viscosity is 6 Pa/s through a vertical 8 mm by 300 mm straw? Assuming Poiseuille flow, what would the flow rate be through a 150 mm straw?

3) Consider an intramuscular injection against 1800 Pa of muscle pressure from a 1 cm diameter syringe through a 260 µm (31 ga.) needle. What force is required to push the plunger of the syringe for a flow rate of 0.15 cm3 /sec? First, assume inviscid flow with a density of 1000 kg/m3 . Second, account for viscous losses (with viscosity of 0.001 Pa s) in the 2.5 cm long needle but assume all other viscous losses (e.g. in the barrel of the syringe) are negligible.

4) Consider a simple model of flow in the aortic arch. Assume an inlet and outlet diameter of 4 cm and uniform inflow/outflow velocities 0.05 m/s. Assume Pin = 24 kPa and Pout 20 kPa and a density of 1060 kg/m3 . What force, F, does the tissue need to exert to keep the arch in place?