The Fluid States

Bernoulli’s Principle

Kristen Reiterwater droplets. 28 Sept. 2010. Flickr. N.p., n.d. Web. 10 Jan. 2011.      <http://www.flickr.com/photos/58002001@N02/5333065857/>.

-Fluids in Motion-o Bernoulli’s Principle explains the effect motion has on a fluid’s pressure and velocity.

-Forces Within Liquids-

o Electromagneticforces in liquidsaffect the way fluidsact.

Diaz, Ryan. Tubular. 2 Feb. 2008. Flickr. N.p., n.d. Web. 10 Jan. 2011.      <http://www.flickr.com/photos/ryandiaz/2241131106/>.

Fluidsin

Motion

Seashore. 28 Oct. 2010. Flickr. N.p., n.d. Web. 11 Jan. 2011.<http://www.flickr.com/photos/52445777@N06/ 5134797287/>.

Bernoulli’s Principle

as the velocity of a fluid increases, the pressure decreases (or vice versa)

higher velocity → lower pressure

narrower space → higher velocity

lower velocity,

higher pressure

higher velocity,

lower pressure

Net Work

Net work is the overall work being done.

(In this case, to move a fluid.)

Tapp, Philip. Nets. 30 Jan. 2010. Flickr. N.p., n.d. Web. 11 Jan. 2011. <http: //www.flickr.com/ photos/philtapp/ 4315913808/>.

Streamlines

narrow flow → closer streamlines → greater velocity → lower pressure

Jumbled or unsmooth streamlines mean the fluid is turbulent and Bernoulli’s Principle does not apply.

o Represent the flow of fluid around objects.

Streamline. 3 July 2009. Flickr. N.p., n.d. Web. 11 Jan. 2011.      <http://www.flickr.com/photos/icajoleu/4114229446/>.

Forces Within Liquids

Rav Productions. Ocean Curl. 27 Jan. 2007. Flickr. N.p., n.d. Web. 11 Jan. 2011.      <http://www.flickr.com/photos/ravpro/385243666/>.

Cohesive Forces

Particles that affect the behavior of liquids

Attract each other with electromagnetic force

Surface Tension

Surface of a liquid to contracts to the smallest possible area

On the surface particles are not attracted upwards

This creates a net downwards pressure

Also causes spherical droplets

Adhesion

Attractive force between different substances

Electromagnetic force

Capillary Action

Rise of liquid in a narrow glass tube

Because adhesive forces are stronger than the cohesive forces

Evaporation

When fast moving particles break through the surface layers of a liquid

Only most energetic particles escape

Has a cooling effect

Volatile Liquids

Volatile liquids evaporate quickly

Have weak cohesive forces

More noticeable cooling effect

Condensation

Evaporated particles returning to liquid state

Cause by decrease in temperature or kinetic energy

Makes the air humid

Quick Review!

Bernoulli’s Principle means higher velocity = lower pressure Cohesive forces are forces that attract particles in a liquid to each other, and cause surface tension

Capillary action is when a liquid “climbs” a glass tube, a result of adhesion.

Quick Review!

Evaporation is when fast moving particles escape the surface of a liquid.

Volatile liquids evaporate quickly!

Condensation is when evaporated liquids cool down or lose energy and become liquid again.

Works Cited

Zitzewitz, Paul W. Physics Principles and Problems. 2002 ed. New York: Glencoe, 2002. Print.