Using Bernoulli's theorem,
PA+21ρVA2=PB+21ρVB2...(i)
Using equation of continuity,
AAVA=ABVB
So, 1.5×10−4×VA=25×10−6×VB
VA=1.5×10−425×10−6×0.6
=101ms−1
Substituting in equation (i)
⇒PA−PB=21000[0.62−0.12]=21000×0.7×0.5
=175Pa
JEE Main 2023 — Physics Mechanics

The figure shows a liquid of given density flowing steadily in horizontal tube of varying cross-section. Cross-sectional areas at A is 1.5cm2, and B is 25mm2, if the speed of liquid at B is 60cms−1 then (PA–PB) is
(Given PA and PB are liquid pressures at A and B points.
Density ρ=1000kgm−3
A and B are on the axis of tube)
Held on 13 Apr 2023 · Verified 6 Jul 2026.
135Pa
27Pa
175Pa
36Pa
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