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Physics 11

FluidsPressureBuoyant ForceIdeal FluidsEquation of ContinuityBernoulli’s Principle

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Fluids in Motion

⇒ The motion of real fluids is very complicated and is not yet fully understood.

⇒ We will only discuss the motion of ideal fluids.

Ideal Fluids1) Steady Flow: the velocity of the moving fluid at any fixed point does not change with time (not turbulent)

Ideal Fluids

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Ideal Fluids2) Incompressible Flow: the fluid is incompressible (density is constant)

3) Nonviscous Flow: friction within the fluid can be ignored

4) Irrotational Flow: a tiny test body placed within the fluid will not rotate about an axis through its own center of mass

The equation of continuity:

ρ1A1 v1 = ρ2A2 v2

⇒ the flow speed increases when we decrease the cross-sectional area

A1 v1 = A2v2 (if ρ constant)

Applications of Bernoulli’s Equation Applications of Bernoulli’s Equation

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Applications of Bernoulli’s Equation Applications of Bernoulli’s Equation

Applications of Bernoulli’s Equation Applications of Bernoulli’s Equation

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Applications of Bernoulli’s Equation