Chapter 13 Lesson 1 - PowerPoint PPT Presentation

1 / 20
About This Presentation
Title:

Chapter 13 Lesson 1

Description:

Chapter 13 Lesson 1 Pressure I. Pressure A. Def the amount of force exerted over an area. 1. Tires gases push on the outside walls of tires B. Formula ... – PowerPoint PPT presentation

Number of Views:137
Avg rating:3.0/5.0
Slides: 21
Provided by: Centra164
Category:

less

Transcript and Presenter's Notes

Title: Chapter 13 Lesson 1


1
Chapter 13Lesson 1
  • Pressure

2
I. Pressure
  • A. Def the amount of force exerted over an
    area.
  • 1. Tires gases push on the outside walls of
    tires
  • B. Formula - P F / A
  • C. Measured in Pascals (N/m2)
  • 1. 101.3 kPa at Sea level
  • 2. 1000 Pa 1 kPa

3
  • D. Our Atmosphere
  • 1. Gas layer that covers the earth.
  • 2. Perfect amount of gases
  • a. Nitrogen 78
  • b. Oxygen 21
  • c. Carbon Dioxide - .04
  • d. Water vapor, dust, argon
  • 3. Air pressure ?s as altitude increases
  • (Indirect)

4
  • E. A book has a force of 30 Newton's while
    resting on a table. If the area of the book is
    0.06 m2, how much pressure does the book exert?
  • P F / A
  • 30 N / 0.06 m2
  • 500 Pa
  • Or 0.5 kPa

5
Chapter 13Lesson 2
  • Forces and Pressures in Fluids

6
I. Pascals Principle
  • A. Def a pressure applied to a fluid is
    transmitted throughout the whole fluid.
  • 1. Squeezing toothpaste
  • 2. Squeezing one end of a
  • balloon
  • B. Hydraulic Machine uses oil like liquid to
    multiply input force up to 10x.

7
II. Bernoullis Principle
  • A. Def as the velocity of a fluid increases,
    the pressure of the fluid decreases.
  • 1. Ex blowing 2 pop cans.

8
  • 2. Airplanes (pg. 213)

Low Pressure
High Pressure
High to Low causes lift for an airplane
9
  • As the airplane speeds down the runway, air
    rushes over and under the wings. The air, going
    over the wings, goes faster and faster, there is
    less and less pressure above the wings. Soon
    there is much more pressure below the wings than
    above. This pressure pushes up on the wings and
    the airplane is lifted into the sky.

10
DEMO
  • -Fill a beaker or cup full of water to the brim.
  • -Add one drop of food coloring
  • -Insert a straw to the middle of the beaker
    vertically.
  • -Blow across the top of the straw. Notice the
    water inside of the straw.
  • -What happens and why?

11
  • 3. Venturi Effect
  • a. Def reduced air pressure outside of
    skyscrapers has caused windows to be blown out.

12
High Pressure
High Pressure
Low Pressure
13
  • 13.2 Assignment Write a paragraph for why a
    curve ball in baseball demonstrates the
    Bernoulli Principle.

14
Chapter 13Lesson 3
  • Buoyancy

15
  • What Archimedes realized about buoyancy
    Archimedes solved many problems for King Heiro of
    Syracuse. His most famous solution is associated
    with Heiro's new crown. Heiro had given the
    goldsmith the exact amount of gold needed for the
    crown. After it was made, Heiro suspected that it
    might not have as much gold as it was supposed
    to. King Heiro summoned Archimedes, and
    Archimedes was bewildered with the king's
    problem. But later, when Archimedes got into his
    full bathtub, it occurred to him that the volume
    of water that spilled out of the tub was equal to
    the volume he displaced. Reasoning that a much
    lower volume of water would be displaced by
    something denser (like gold) even though of equal
    weight, he saw the answer to the king's problem.
    The next day Archimedes told they king of his
    discovery. Archimedes put the king's new crown in
    a tub of water and found that the crown indeed
    displaced more water than the same weight of gold
    (it occupied more volume because it had been
    adulterated with lower density silver). The
    goldsmith was immediately beheaded.

16
  • I. Buoyancy
  • A. Def the ability of a fluid to exert an
    upward force on an object placed in it.
  • 1. results in an apparent loss of
    _________
  • ? easy to lift
  • ? opposite of gravity
  • B. History
  • 1. Archimedes's Principle
  • ?the buoyant force on an object is equal to
    the weight of fluid displaced by the object.

Weight
17
  • In other wordsthink of the clay activity we did
    earlier in this chapter.

18
  • C. Two Ways to tell if an object can float
  • 1. Density
  • gt 1
  • lt 1
  • 2. Force Analysis
  • ? weight vs. buoyant force
  • weight gt buoyant force
  • weight lt buoyant force

sink
float
sink
float
19
  • weight buoyant force
  • suspended

20
Quiz Review Content
  • Know Pascals Principle and what it applies to.
  • Know the pressure equation and units
  • What is the definition of a fluid?
  • What is the relationship between altitude and
    pressure?
  • Know Bernoullis Principle and what it applies
    to.
  • Know what the Venturi Effect is.
  • Be able to calculate force, area, and pressure.
    SHOW YOUR WORK!!!!!
  • There is also an extra credit question on the
    quiz, but you will have to get it right to get
    the extra credit.
Write a Comment
User Comments (0)
About PowerShow.com