Physics · Fluid Dynamics
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Water flows through a constriction in horizontal pipe as it enters the constriction, the water's:
- A
Speed increases and pressure remains constant
- B
Speed increases and pressure increase
- C
Speed increases and pressure decreases
- D
Speed decreases and pressure Increases
We know that the volume flow rate (Avt) is constant, with V/v = A, we know that Area is directionally proportional to velocity. ‘Constriction’ tells us that the area has decreased, thus the speed increases.
According to Bernolie’s theorem P + pgh + 1/2 = constant.
Value for pgh is constant as it depends on height, the value for 1/2pv2 increases as velocity increases, thus to maintain the constant the value of pressure must decrease.
Pressure decreases, not remains constant.
Pressure decreases, not increases.
When flowing through a constricted area of a pipe, a fluid's velocity increases and its static pressure decreases. This principle is known as the Venturi effect. Fluids speed up when they reach a constriction to maintain a constant volume flow rate.
Speed increases, not decreases.
Tagged under Physics · Fluid Dynamics · 2015