Question

In a horizontal tube of diameter 2mm and length 100cm water flows at the rate of 60cc in 10 minutes against viscous drag. If n= 10 poise. Calculate the force required to mantain the flow.

Answer 1

Answer:

given = diameter = 2mm

             length =  100cm

             rate = 60cc

             time =  10min

             n = 10 poise

to fine = force

solution  =  

                    for radius = d /2 = 2mm / 2 = 0.1cm

                    length = l = 100cm

                  volume per second

                  V= 60 / 10 x 60= 1/10cm³s⁻¹

                  η = 10poise

                  F = 8ηlV/r²

                  F = 8 X 10 X 100/ (0.1)²X 1/10= 80,000dyne .

the force required to mantain the flow.80,000dyne .