Determine the speed V at which the cylinder must be pushed down into the tube so that the liquid in the tube rises with an average velocity of 4 m/s. Water flows into the rectangular tank through...

Determine the speed V at which the cylinder must be pushed down into the tube so that the liquid in the tube rises with an average velocity of 4 m/s.

Water flows into the rectangular tank through pipes A and B, with velocities of 4 m/s and 2 m/s, respectively. Determine the rate at which the surface of the water is rising. Ignore the effect of gravity on the falling water.