Physics with Trig I

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Physics with Trig I
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Where weve been

• 1-D Motion
• Vectors and 2-D Motion
• Newtons Laws of Motion
• Work Energy
• Conservation of Momentum
• Circular Motion Gravity
• Torque Angular Acceleration

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Ch 9 Introduction
Matter in bulk comes as solids and fluids, both
liquid and gas forms. An understanding of fluids
is particularly important to students going into
the life sciences. Liquids have a fixed volume
but no definite shape whereas gases have neither
volume nor shape.
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Where were going
Ch 9 Solid Fluids (9.3) Density
Pressure (9.4) Variation of Pressure with
Depth (9.5) Pressure Measurements (9.6) Buoyant
Forces Archimedess Principle (9.7) Fluids in
Motion
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(9.3) Density Pressure
Mass density ?
See Table 9.2, page 262
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(9.3) Density Pressure
Relative Density ?
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(9.3) Density Pressure
Units of pressure
See Figure 9.15, page 267
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(9.4) Variation of Pressure with Depth

• All points at the same depth are at the same
  pressure.

Atmospheric Pressure
Pressure caused by the fluid
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(9.4) Variation of Pressure with Depth

• All points at the same depth are at the same
  pressure.

Units
Force
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(9.4) Variation of Pressure with Depth,
Pascals Law A change in P applied to a fluid is
transmitted undiminished to every point in the
fluid and walls of the container.
Example Hydraulic lift Picture pg. 266
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(9.5) Pressure Measurements
Read about Blood Pressure Measurements.

• Gauge vs. Absolute pressure
• Absolute pressure is the absolutely the truth
  about the pressure being measured.
• Gauge pressure P gauge P Absolute P
  atmospheric

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(9.6) Buoyant Forces Archimedess Principle
B ? Buoyant Force weight of the displaced
fluid. Weight can be written as
Units
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(9.6) Buoyant Forces Archimedess Principle
B ? Buoyant Force weight of the displaced
fluid. Weight can be written as

• Problem 9-26
• Buoyancy Demo

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(9.7) Fluids in Motion
So, flow rate flow rate That is, flow rate
through a pipe is constant. Problem 9.40
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The End