Ch. 8 Quiz (8A-8B)

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What important property of fluids necessitated the development of fluid mechanics as an area of science separate from standard mechanics?
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What important property of fluids necessitated the development of fluid mechanics as an area of science separate from standard mechanics?
Fluids lack rigidity so physicists developed special mechanical principles to account for their behavior
How is pressure calculated? How does pressure change when each of its contributing factors is increased?
By dividing the force exerted perpendicular to a surface by the services area/pressure increases as the force increases and pressure decreases as area increases
How does pressure exerted by a solid object on a surface differ from pressure exerted within a liquid or gas?
The pressure exerted by a solid object results from a net force exerted perpendicular to the surface that the object touches. Pressure at a point within a fluid is exerted equally in all directions
What is the derived unit of pressure in the SI? To what combination of SI units is it equal? What pressure unit is used in weather prediction
Pascal/newtons per square meter/ air pressure in millibars
Discuss the difference between gauge pressure and absolute pressure. What is a gauge pressure of zero equivalent to?
Gauge pressure measures system pressure relative to atmospheric pressure; absolute pressure measures pressure relative to a perfect vacuum/zero gauge pressure indicates that the system is at atmospheric pressure
What two factors affect the pressure in a fluid? How does gravity affect each of these? What to aspects of a fluid container do not affect fluid pressure?
Density and the depth at which the pressure is measured/gravity significantly affects the density of gases but has little effect on liquid density; density in gravity vary measurably with height/shape and volume
State Archimedes's principle in your own words.
And object immersed in a fluid is lifted or buoyed up by a force equal to the weight of fluid that it displays
List three kinds of buoyancy by comparing the densities of the fluid and the object in the fluid. Describe what happens to the object in each case.
Positively buoyant if it is less dense than the fluid itself, naturally buoyant if it's densities is equal to that of the fluid, and negatively buoyant if its density is greater than that of the fluid
Why is specific gravity useful?
It is useful classification property for liquids and solids his density vary predictively with composition
(True or False) If a mercury barometer were taken into a deep mine on a typical day, the mercury column would probably be taller than 760 mm.
True
How did pascal explain the bursting of the waters cask's staves and his experiment?Pascal reasoned that changes in pressure were distributed equally throughout the fluidWhat conditions must exist for Pascal's principle to be true? What real fluids seem to obey Pascal's principle fairly well?1. It must be confined 2. It must be incompressible/water like fluidsWhat do we call a mechanical device that uses a fluid to make work easier? And what principle do these devices rely?Hydraulic machines/principle of hydraulicsA simple hydraulic machine uses pistons to apply a force to a fluid and to exert a force to do work. What is one way to commute the IMA of a simple hydraulic machine?Dividing the surface area of the load piston by the surface area of the effort piston/dividing the distance that the effort piston moves by the distance that the load piston movesWhat is the most important condition that must exist for a fluid to flow? In a piping system, what other factors affect the flow of a liquid?A pressure difference between points in a fluid that is capable of flowing/the pipe size, liquid density, liquid viscosity, and how smoothly the liquid flowsAccording to Bernoulli's principle, the combination of what three properties of a liquid flowing in a pipe must be the same at all points in the pipe? What factors to prevent this principle from being extroverted true in real-world flowing liquids?Liquids pressure, kinetic energy, and potential energy/friction and liquid viscosity(True or False) A manually operated hydraulic jack applies the Bernoulli principle to amplify effort to do work.False