Question

1.A hypodermic needle of lenght 0.020m and inner radius 3.0 x10^-4 is used to force water at 20 degree celcious into the air at a flow rate of 1.0 x10^-7m^2 s-1 (a) what is the average velocity in the needle?(assume laminar flow), (b) what is the pressure drop necessary to achieve the flow rate?
2. An artery has an inner radius of 2.0 x 10^-3m. if the temperature is 37 degree celcius, the average velocity of the blood is 0.030ms^-1 and the flow is laminar flow. find (a)the maximum velocity, (b) the flow rate and (c) the pressure drop in 0.050m, if the artery is horizontal.