A jet of cross-sectional area A1 steadily issues fluid density at a velocity V1, into a duct of area A2=5A1, as shown in the illustration below. The jet has parallel streamlines. The surrounding flow in the duct as the same density and a velocity V2=(1/2) V2 .The flow mixes thoroughly, and by section B the flow is approximately uniform across the duct area. In terms of p and V1, find the average velocity of flow at section B, and the pressure difference between sections A and B.