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11/16/09 - Pressure and Density, Change of Pressure with Depth, Pascal's Principle and Archimedes's Principal
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 | Pressure is the result of spreading a force over an area
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| Density is mass (or weight) per unit volume
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 | Density of water = 1 g/mL = 1g/cm3 = 1000 kg/m3 = 62.4 lb/ft3
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| Density of aluminum = 2.7 g/cm3 = 2700 kg/m3
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| Density of mercury = 13.6 g/cm3 = 13600 kg/m3
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| 1 atm = 1.01x105 N/m2 = 1.01x105 Pa = 760 mm Hg = 14.7 psi
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| Pressure increases with depth
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| P = Dgh = Density*gravity*depth
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| Pascal's Principle - Pressure is the same in all directions
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| Pressure as a force multiplier
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| Archimedes's Principal - Sink or Float?
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| Objects which sink displace their volume of liquid.
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| The buoyant force on a submerged object equals the weight of fluid displaced.
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| Objects which float displace their weight of liquid.
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| The buoyant force on a floating object equals the weight of fluid displaced equals the weight of the floating object.
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| Read pp. 309-328 of the text.
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