8th Grade Chapter 4 Lesson 1

  • 640 views
Uploaded on

For Student Use Only

For Student Use Only

More in: Technology , Business
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
No Downloads

Views

Total Views
640
On Slideshare
0
From Embeds
0
Number of Embeds
0

Actions

Shares
Downloads
0
Comments
0
Likes
2

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Pgs. 138-144 For Student Use Only
  • 2.
    • Fluids:
      • NOTE:
        • Water and Air are fluids
        • Fluid means flowing.
        • They pass freely from one place to another
        • Fluids are different than solids because they can flow
  • 3.
    • Characteristics:
      • Liquids- definite volume, but NO definite shape
        • Fit into a container but will NOT expand to fill it
      • Gases- NO definite volume, NO definite shape
        • Will expand to fill a container and take shape of container
  • 4.
    • John Dalton
      • Built upon Greek knowledge and said that all matter is made up of particles called atoms that combine to make molecules
      • ATOMIC THEORY OF MATTER:
        • All matter is made up atoms that can combine
  • 5.
    • Daniel Bernoulli:
      • Helped build foundation of our understanding of molecules
      • Led to the KINETIC THEORY OF MATTER
        • KTM= The molecules of matter are in constant motion
      • Molecules in:
        • Solids= vibrate without much movement
        • Liquids= move randomly
        • Gas= move farther and faster
  • 6. http://www.ilpi.com/msds/ref/gifs/statesofmatter.gif
  • 7.
    • Mixing of Molecules:
      • Diffusion= the mixing of molecules of one kind with molecules of another kind
      • Diffusion occurs in liquids and in gasses
      • Diffusion occurs because particles run into each other
  • 8.
    • Molecules Stick Together:
      • Cohesion= the ability of molecules of the SAME kind to stick together
      • Adhesion= the ability of different kinds of molecules to stick together
        • Identify:
          • Water sticking to water
          • Corn syrup sticking to plate
          • Dog hair sticking to your clothes
  • 9.
    • Water’s Cohesion:
      • Water molecules are attracted to each other
      • Water molecules on the surface are attracted to the molecules on the side or underneath
      • This creates a “film” on top of water.
      • SURFACE TENSION= tendency of liquid to act as if it has a thin film on top
  • 10. http://www.mtbaker.wednet.edu/harmony/ditch/images/water_1.jpg
  • 11.
    • Surface Tension
      • Causes particles to form spheres (bead up)
        • Gravity turn spheres into mounds
      • Can allow objects more dense than water to float
      • Forms a meniscus
        • Meniscus= where the water rises on the glass
  • 12.
    • Working Together:
      • The meniscus forms because the adhesion (glass to water) is stronger than the cohesion (water to water)
    • CAPILLARY ACTION:
      • When a liquid in a thin tube falls above or below normal level
        • Water is pulled up a small glass tube by adhesion
        • Mercury is not as attracted to glass and is more attracted to itself
  • 13.
    • Comparing Density:
      • How do you calculate density?
        • Density= mass/ volume
          • Grams/mL
      • Densities of many objects can be compared
      • Densities are usually compared to water
  • 14.
    • Specific Gravity:
        • Specific Gravity= a number that compares the density of an object with that of water.
          • In other words= zinc has a specific gravity of 7 and is 7 times as dense as water
        • Specific Gravity= Density of object/ Density of water
  • 15.
    • Pressure:
      • Pressure= the force exerted per unit of area
        • Water Pressure= the pressure water exerts on you
      • Pressure= Force/ Area or P=F/A
        • PSI= Pounds per Square Inch
      • The air weighs only a little, but exerts much pressure
  • 16.
    • Compression Pressure:
      • A fluids’ container can cause pressure changes
      • Pressure is spread out evenly
      • Pressure is caused by the squeezing of a fluid into a container
    • Depth and Pressure
      • Gravitational Pressure can cause changes as depth increases (more pressure)
        • Gravity pulls down on objects
        • NOTE: gravitational pressure in fluids is spread evenly in all directions