Fluids ii
Download
1 / 12

Fluids II - PowerPoint PPT Presentation


  • 60 Views
  • Uploaded on

Fluids II. F b. mg. Mg. Archimedes Example. A cube of plastic 4.0 cm on a side with density = 0.8 g/cm 3 is floating in the water. When a 9 gram coin is placed on the block, how much sinks below water surface?. h. 12. Question.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Fluids II' - garrett-potts


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Archimedes example

Fb

mg

Mg

Archimedes Example

A cube of plastic 4.0 cm on a side with density = 0.8 g/cm3 is floating in the water. When a 9 gram coin is placed on the block, how much sinks below water surface?

h

12


Question
Question

Suppose you float a large ice-cube in a glass of water, and that after you place the ice in the glass the level of the water is at the very brim. When the ice melts, the level of the water in the glass will:

1. Go up, causing the water to spill out of the glass.

2. Go down.

3. Stay the same.

Must be same!

14


Archimedes principle
Archimedes’ Principle

  • If object is floating…

8


Archimedes principle1
Archimedes’ Principle

  • Which picture looks like an ice cube floating?…

B

C

A

8



Question 2

Tub of water + ship

Tub of water

Overflowed water

Question 2

Which weighs more:

1. A large bathtub filled to the brim with water.

2. A large bathtub filled to the brim with water with a battle-ship floating in it.

3. They will weigh the same.

Weight of ship = Buoyant force =

Weight of displaced water

16


Fluid flow concepts

r

A1P1

v1

A2 P2

v2

Fluid Flow Concepts

  • Mass flow rate: Av (kg/s)

  • Volume flow rate: Av (m3/s)

  • Continuity: A1 v1 = A2 v2

    • i.e., mass flow rate the same everywhere

    • e.g., flow of river

21


Bernoulli s eq and work

r

A1P1

v1

A2 P2

v2

Bernoulli’s Eq. And Work

  • W = DK + DU

  • W=F d = PA d = P V

    (P1-P2) V = ½ m (v22 – v12) + mg(y2-y1)

    (P1-P2) V = ½ rV (v22 – v12) + rVg(y2-y1)

    P1+rgy1 + ½ rv12 = P2+rgy2 + ½rv22

    Compare P1, P2

33


Example lift a house
Example: Lift a House

Calculate the net lift on a 15 m x 15 m house when a 30 m/s wind (1.29 kg/m3) blows over the top.

48



Fluid flow summary

r

A1P1

v1

A2 P2

v2

Fluid Flow Summary

  • Mass flow rate: Av (kg/s)

  • Volume flow rate: Av (m3/s)

  • Continuity: A1 v1 = A2 v2

  • Bernoulli: P1 + 1/2v12 + gh1 = P2 + 1/2v22 + gh2

50


ad