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Flashcards in C8 Terms Deck (41):
1

The study of how fluids flow and how forces and energy are transmitted through fluids

Fluid mechanics

2

The ratio of forces to the area

Pressure (P)

3

A pressure is exerted equally in all directions

Fluid pressure

4

The SI base unit of pressure

pascal (Pa)

5

Water pressure due to depth

hydrostatic pressure

6

A thick walled glass tube filled with liquid mercury and sealed on one end

mercury barameter

7

Contains a accordion like can filled with a low pressure gas

aneroid barometer

8

Fluid pressures is measured with?

gauge

9

An immersed object is lifted or buoyed up by a force equal to the weight of the fluid displacement. This is called the buoyant force

Archimedes' principle

10

States that an immersed object is lifted up by a force equal to the weight of the fluid displaced

buoyant force

11

Comparing the density of an object to the density of water

specific gravity

12

Changes of pressure on a fluid are exerted equally throughout the fluid

Pascal's principle

13

Hydraulic machine

They produce MA by magnifying a small force on a confined liquid to make a large force on the load

14

Hydraulics

Using a liquid to exert a force

15

Bernoulli's principle

Pressure In a pipe is related to he waters height and it's velocity

16

Venturi

A pressure meter that uses flow

17

Lift

An upward force p

18

Coanda effect

The diverting of the path of water flowing around a cylinder

19

Air foil

Any surface that is designed to deflect air or create a force as it moves though the air

20

Boyle's law

The inverse relationship between the volume and pressure of a confined gas

21

Charles law

The volume of a fixed amount of gas changes in the same way as it's absolute temperature

22

What property of fluids necessitated the development of fluid mechanics as an area of science separate from standard mechanics?

Because they have special physical properties such as lack of rigidity.

23

How is pressure calculated?

Pressure is calculated using the formula

F
P=----
A

Where
• P is pressure in newtons per square meter
• F is the net force acting perpendicular to the surface in newtons
• A is the total surface area over which the force is applied

24

How does pressure change when each of its contributing factors is increased?

When force is increased the pressure rises. When the area is increased the pressure goes down.

25

How does pressure exerted by a solid object on a surface differ from pressure exerted within a liquid or a gas?

Liquids and gases exert pressure in all directions and a solid can only exert a pressure in one direction

26

What combination of SI units is the pascal equal to?

Newtons per square meter

27

What pressure unit is used in weather prediction?

The bar

28

What 2 factors affect the pressure in a fluid?
How does gravity affect each of these?

Depth and density

If there was no gravity the depth would not make a difference. Gravity pulls down on the particles and compresses the ones that are below the surface

29

What 2 aspects of a fluid do not affect fluid pressure?

Shape and volume

30

List the 3 kinds of buoyancy

Objects the float objects the sink, and objects that hover

31

Why is specific gravity useful?

It is useful as an identifying property of substances especially solutions and other mixtures

32

(T/F) If a mercury barometer were taken into a deep mine on a typical day, the mercury column would probably be taller than 760 mm.

False

33

What conditions must exist for pascal's principle to be true?

The fluid must be totally contained
The fluid must be incompressible

34

What is one way to compute the ideal MA of a simple hydraulic machine?

Divide the area of the resistance piston be the area of the effort piston

35

What is the most important condition that must exist for a fluid to flow?

Pressure

36

(True or false) A manually operated hydraulic jack applies the Bernoulli principle to amplify effort to do work.

False

37

Research in gases lead to the acceptance of what principal theory of science.

The theory of particle matter

38

What three factors contribute to gas pressure.

Temperature, the number of gas molecules in a volume of gas, and the number of collisions per second

39

If the volume of a confined gas triples what happens to the gas's pressure?

It will be one third of the original pressure

40

When a confined gas experiences a temperature change which of the three factors from the question above could change the pressure of the gas?

The speed of the molecules

41

(True or false) An oxygen molecule has eight times as much mass as a hydrogen one.

False