Water flows steadily through a pipe whose diameter decreases from 6 cm to 3 cm. If the speed in the wider section is 2 m/s, the speed in the narrower section is N m/s. Find N.
Physics · Fluid Mechanics · equation of continuity and bornullie theorem
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Question

Water flows steadily through a pipe whose diameter decreases from 6 cm to 3 cm. If the speed in the wider section is 2 m/s, the speed in the narrower section is N m/s. Find N.

G1 Physics · Accepted Answer

For incompressible flow, A₁v₁ = A₂v₂. Area is proportional to the square of diameter. Therefore, A₁/A₂ = (d₁/d₂)² = (6/3)² = 4. Hence, v₂ = (A₁/A₂)v₁ = 4×2 = 8 m/s. Thus, N = 8.