- #1

- 5

- 0

i.e. -----------

- -

- -

del t1 |3 minutes | del t2

(just like a trapezium without the bottom part), and del t1=del t2. Pumping power is decreasing from t=0 to t=4minutes and pumping power =0 when t>4 minutes.

Is it accurate if we try to explain this observation as follows:

Due to conservation of momentum, the rate of momentum-changing force per unit area, dP1/dt, produced by the pump is balanced by an equivalent negative rate of momentum-changing force per unit area, -dP2/dt produced by the system after 3 minutes at x=0.

Thank you very much for your kind assistance.

Sarah