This document discusses fluids and Bernoulli's principle in physics. It defines ideal fluids as those with steady, incompressible, nonviscous, and irrotational flow. It presents the equation of continuity which states that the density times area times velocity is constant for a fluid. Bernoulli's principle states that as the flow speed of a fluid increases, the pressure decreases, which has various applications such as in aircraft wings and Venturi tubes.

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Physics 11
Fluids
Pressure
Buoyant Force
Ideal Fluids
Equation of Continuity
Bernoulli’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 Fluids
1) 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 Fluids
2) 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

5. 5
Applications of Bernoulli’s Equation