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P&P 13 States of Matter• In this chapter we will combine ideas from the

last chapter on thermal physics with the various states of matter. exploration.grc.nasa.gov/.../rocket/state.html

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Assignment

13/3,8,9,26,30,31,34,35,40,42

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Fluids - liquids and gases

Pressure = Force = F N Pascal or Pa Area A m2

Standard atmosphere = 1.01325x105Pa10N/cm2 or 10-4N/m2

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Gas Laws

• Combined Gas Law

1 – original values2 – new values

P, Pressure, PaV, Volume, Liter, LT, Temperature, K

P1V1 = P2V2

T1 T2

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Ideal Gas Law

PV = n RTP, pressure, PaV, volume, Ln, number of moles or moleculesR, universal gas constant: 8.31 Pa m3/mol KT, temperature, K

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• Assignment:• 13/3,8,9

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Pascal’s Principle

If an external pressure is applied to a confined fluid, the pressure at every point within the fluid increases by that amount.F2 F1

A2 F2

F, force, newtons, NA, area, m2

=

http://www.cord.edu/dept/physics/p128/Images/Pascal_principle.gif

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http://www.engineering.com/content/community/library/sciencelaws/pascalslaw/images/variation_depth.jpg

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Buoyant Force• Fbuoyant = fluid Vg , density for water, 1.00 x 103 kg/m3

• v, volume, m3

• g, gravity, 9.8 m/s2

“The buoyant force on an object is equal to the weight of the fluid displaced by the object, which is equal to the density of the fluid in which the object is immersed multiplied by the object’s volume and the acceleration due to gravity. (page 354)

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Archimedes’ Principle

• “An object immersed in a fluid has an upward force on it that is equal to the weight of the fluid displaced by the object. The force does not depend on the weight of the object, only on the weight of the displaced fluid.

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http://home.earthlink.net/~divegeek/archimedes_files/buoyancy.gif

http://www.stormyseas.com/images/buoyancy.jpg

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P = h gPressure at any depth is proportional to the fluid’s weight

above that depth.P, pressure, Pascal or N/m2

, density, kg/m3

h, depth of object, m

http://www.flow-guard.com/flow-guard-images/breather-bag-images/underwater-well-head.jpg

As depth increases, psi increases. Also fish change with depth.

English psi – pounds per square inch

SI unit: Pascal or N/m2

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Buoyant Force & Archimedes

• 13/26,30,31

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Bernoulli’s Principle

• As the velocity of a fluid increases, the pressure exerted by that fluid decreases.

www.centennialofflight.gov/.../bernoulli/DI9.htm

solomon.physics.sc.edu/~tedeschi/demo/demo21.html

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star.tau.ac.il/QUIZ/05/Q07.05.html

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Solids

• The thermal expansion of a solid is proportional to the temperature change and original size, and it depends on the material.

http://www.scienceclarified.com/images/uesc_10_img0566.jpg

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Coefficient of Linear Expansion,

= L change in length L1 T orig. length, change in

temp

Units: 1/oC or oC-1

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Coefficient of Volume Expansion,

= V change in volume V1 T orig. volume, change in

tempUnits: oC-1

Manufacturing many types of glassware made of heat resistant borosilicate glass or soda lime glass using automatic press machines or manual press.

Borosilicate Glass(Code: TE-32) with thermal expansion coefficient 32.5X10-7/°C

www.atgc.co.jp/div/material/hebin/he3000.html

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Major Applications

• Glass trays for Micro oven • Transparent roof tiles • Glass mixer jars • Glass window for automatic washing machines • Glass lens and reflector for automotive lighting • Glass globes for airport or harbor lighting • Colored lenses for railroad signals • Fly-eye lens for digital projectors

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• 12/40,42