Q.

Water flows through a horizontal tube as shown in the figure. The difference in height between the water columns in vertical tubes is 5 cm and the area of cross-sections at A and B are 6cm2 and 3cm2 respectively. The rate of flow will be ______ cm3/s. (take g = 10 m/s²)      [2026]

1 2003  
2 1003  
3 2003  
4 2006  

Ans.

(3)

From continuity equation

AAVA=ABVB6VA=3VBVB=2VA

Applying Bernoulli's equation between A & B,

          PA+12ρVA2=PB+12ρVB2

ρg×0.05=12ρ[VB2-VA2]=12ρ(3VA2)

VA=2g×0.053 m/s=13 m/s=1003 cm/s

Volume flow rate=AAVA=6×1003cm3/sec

        =2003 cm3/sec