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Bernoulli’s Theorem:

Bernoulli’s theorem is a fundamental principle in fluid dynamics that describes the behavior of an ideal fluid in steady, incompressible flow. Here are the key aspects of Bernoulli’s theorem:

  1. Description:
  • Bernoulli’s theorem states that in a streamline flow of an ideal fluid (non-viscous and incompressible), the sum of the pressure energy, kinetic energy, and potential energy per unit volume remains constant along any streamline.
  • Mathematically, it can be expressed as: \[ P + \frac{1}{2} \rho v^2 + \rho gh = \text{constant} \] where:
    • \( P \) is the pressure of the fluid,
    • \( \rho \) is the density of the fluid,
    • \( v \) is the velocity of the fluid,
    • \( g \) is the acceleration due to gravity,
    • \( h \) is the height above a reference point.
  1. Assumptions:
  • Bernoulli’s theorem assumes steady flow (no changes over time), incompressible flow (density remains constant), and non-viscous flow (no internal friction).
  • It also assumes that the fluid is along a streamline, meaning there is no crossing or mixing of flow lines.
  1. Applications:
  • Bernoulli’s theorem has numerous applications in fluid dynamics, aerodynamics, and engineering:
    • It explains the lift force on aircraft wings.
    • It helps in understanding fluid flow in pipes and channels.
    • It is used in designing hydraulic systems, such as pumps and turbines.
    • It is applicable in understanding blood flow dynamics in arteries and veins.
  1. Limitations:
  • Bernoulli’s theorem applies strictly to ideal fluids under ideal conditions. Real fluids may deviate from ideal behavior due to factors such as viscosity, compressibility, turbulence, and boundary effects.
  • The theorem does not account for energy losses due to friction or heat transfer within the fluid.

Bernoulli’s theorem is a cornerstone in fluid mechanics, providing insights into the distribution of energy within flowing fluids and serving as a basis for practical applications in engineering and science.

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