Question

Oil is flowing in a circular pipe of varying cross-sectional area and at all points the oil completely fills the pipe. (a) At one point in the pipe the radius is 30cm,what is the magnitude of the oil velocity if the flow rate is 1.20mcube/s?

Answer 1

I tried this:

Explanation:

I would use the Continuity Equation (assuming Laminar Flow) stating that the Flow Rate `R` (in `m^3/s`) stays constant along the pipe and it is equal to the product of the velocity `v` times the sectional area `A=pir^2` of the pipe:

`R=Av=const.`

in our case (changing into meters):

`1.2=pi(0.3)^2*v`

rearranging:

`v=4.24m/s`