Strategic Intervention ReferEnce Card Materials on Physicst909

7/27/2019 Strategic Intervention ReferEnce Card Materials on Physicst909

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Prepared by;MARJORIE Q.REFORMAIV-TANIGUE

SEPTEMBER 5,2012


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Hello welcome to the world in pressure is the amount of force exerted onagivenarea


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Pressure calculation. There are many physical situations where pressure is the most important variable. If you arepeeling an apple, then pressure is the key variable: if the knife is sharp, then the area of contactis small and you can peel with less force exerted on the blade. If you must get an injection, thenpressure is the most important variable in getting the needle through your skin: it is better tohave a sharp needle than a dull one since the smaller area of contact implies that less force isrequired to push the needle through the skin.When you deal with the pressure of a liquid at rest , the medium is treated as a continuousdistribution of matter. But when you deal with a gas pressure , it must be approached as anaverage pressure from molecular collisions with the walls.Pressure in a fluid can be seen to be a measure of energy per unit volume by means of thedefinition of work . This energy is related to other forms of fluid energy by the Bernoulliequation .
http://hyperphysics.phy-astr.gsu.edu/hbase/prcal.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pflu.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/kinthe.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/work2.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/work2.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/kinthe.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pflu.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/prcal.html


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http://hyperphysics.phy-astr.gsu.edu/hbase/astro/transp.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/astro/transp.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/diffus.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pflu.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/conser.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/astro/transp.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/astro/transp.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/diffus.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pflu.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/conser.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/press.html


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Fluid Kinetic EnergyThe kinetic energy of a moving fluid is more useful in applications like the Bernoulliequation when it is expressed as kinetic energy per unit volume

When the kinetic energy is that of fluid under conditions of laminar flow through a tube,one must take into account the velocity profile to evaluate the kinetic energy. Across thecross-section of flow, the kinetic energy must be calculated using the average of thevelocity squared , which is not the same as squaring the average velocity. Expressed interms of the maximum velocity v m at the center of the flow, the kinetic energy is
http://hyperphysics.phy-astr.gsu.edu/hbase/ke.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pfric.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pfric.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pfric.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pfric.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/pber.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/ke.html


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Warning all grownups: get your sense of humorready for this science experiment, whichdemonstrates fundamental physics of air pressure.You can do this in a lab, of course, or withtechnical worksheets, but we love this goofymagic trick with a kid and a grownupand anaudience, too, if you dare.

What You Need:

2 plastic drink bottles, 1-2 liters in size, clean anddryLatex balloonsPin or tack


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Pressure Activity scaffolding activity Introduction: Introduction: Though you may not realize it, the air has weight. All the airmolecules in the atmosphere exert a force, or pressure, onour bodies. Atmospheric pressure is the force exerted by the

weight of the air above an object or surface. Variations inpressure generate winds, which play a significant role inday to day weather conditions. The purpose of this activityis to introduce characteristics of pressure, high and lowpressure centers, and a brief analysis of an idealizedpressure field. Key words throughout this activity link

directly to helper resources that provide useful informationfor answering the questions.


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Characteristics of Pressu re: 1) What are the different units of pressure ? Which unit is usedmost by meteorologists? 2) Circle the correct res ponse in the following sentence: Pressure(increases / decreases) with height . Please explain why pressurechanges this way with height.High and Low Pressure Centers: 3) Draw the symbol that represe nts a high pressure center on aweather map. Do the same for a low pressure center .

4) Pictured below are two imaginary columns of air moleculesexerting pressure on the surfaces below them. The left column

contains fewer air molecules than the right column.
http://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/pressure_units.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/pressure_units.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/pressure_units.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/pressure_height.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/pressure_height.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/anticyclone.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/anticyclone.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/pressure_height.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/pressure_units.rxml?hret=/guides/crclm/act/prs.rxml


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Which column is more representative of the atmosphere abovea high pressure center ? Which one is more likely to be found overa low pressure ? Using the correct symbols for labeling high and lowpressure centers (see question #3), mark your answers beneath theappropriate columns in the diagram above. You may label thediagram in one of two ways; 1) by printing out a copy of this

activity and marking your answers directly onto the printout or 2)by saving the image into your favorite graphics software andmodifying the image using that graphics package.
http://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/anticyclone.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/anticyclone.rxml?hret=/guides/crclm/act/prs.rxml


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Analysis of a Pressure Field: 5) The diagram below is an idealized pressure field resembling those commonlyfound on surface weather maps. The numbers along each contour indicate the

pressure value in millibars for that particular contour. Use the diagram below toanswer the following questions.What are the green contours ? What do they represent?
http://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/isobars.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/isobars.rxml?hret=/guides/crclm/act/prs.rxml


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Label th e dia gra m above to indicate the positions ofthe high and low pressure centers. Please use the correct symbols (seequestion #3). You may label the diagram in one of two ways; 1) byprinting out a copy of this activity and marking your answers directlyonto the printout or 2) by saving the image into your favorite graphicssoftware and modifying the image using that graphics package.

Dra w an arrow (on the dia gram above) to indicate the direction in whichthe pressure gradient force is pointing. Examine the Current Pressure Field: 6) Using what you learn ed in q uestions 1-5, open the following map andcreate the la test map of isobars . On this map, mark the positionsofhigh and low pressure centers (using the correct symbols).

You may label your image in one of two ways; 1) by printing out a copyof the image and marking your answers directly onto the printout or 2) bysaving the image into your favorite graphics software and modifying theimage using that graphics package.
http://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/anticyclone.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/anticyclone.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/pressure_gradient.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/pressure_gradient.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/isobars.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/anticyclone.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/isobars.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/anticyclone.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/anticyclone.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/isobars.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/pressure_gradient.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/low_pressure_center.rxml?hret=/guides/crclm/act/prs.rxmlhttp://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/anticyclone.rxml?hret=/guides/crclm/act/prs.rxml


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1.What is the pressure of the cylinder?


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1.what happened

Pressure=force/area


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Strategic Intervention ReferEnce Card Materials on Physicst909