Physics #4

Question 1

the ratio of mass to volume is ____

Answer 1

density

Question 2

1 cubic cm = ____ mL

Answer 2

1

Question 3

1 cubic m = ______ L

Answer 3

1000

Question 4

what is the density of water

Answer 4

1 g/cm^3 OR 1000 kg/m^3

Question 5

1 Pascal = ____

Answer 5

1 N/m^2

Question 6

is pressure a vector or a scalar?

Answer 6

it is a scalar because it is equal throughout the container of the fluid.

Question 7

at higher altitude is there more or less atmospheric pressure?

Answer 7

less

Question 8

what is a synonym for absolute pressure?

Answer 8

hydrostatic pressure

Question 9

what is absolute pressure?

Answer 9

the total pressure that is exerted on an object that is submerged in a fluid.

Question 10

____ is the study of fluids at rest and the forces and pressures associated with standing fluids

Answer 10

hydrostatics

Question 11

how does a body of water react to high pressure or low pressure system above it

Answer 11

high pressure system: valley in body of water

low pressure: mountain in body of water

Question 12

Pascal’s principle of hydrostatics, or Pascal’s law, states that ____

Answer 12

the pressure exerted anywhere in a confined incompressible liquid is equally transmitted throughout the fluid.

Question 13

In Pascal’s principle, the larger the area the _____ the force over the _____ distance

Answer 13

larger

smaller

Question 14

Archimede’s principle

Answer 14

a body wholly or partially immersed in a fluid will be buoyed upwards by a force equal to the weight of the fluid that it displaces

Question 15

An object will only be as submerged in water to the point where the volume of displaced water produces a force _______ to the weight of the object

Answer 15

equal

Question 16

_____ causes the liquid to form a thin but strong layer like a skin at the liquids surface

Answer 16

surface tension

Question 17

cohesion

Answer 17

the attractive force that a molecule of a liquid feels toward other molecules of the same liquid

Question 18

adhesion

Answer 18

the attractive force that a molecule of liquid feels toward the molecules of some other substance.

Question 19

when does a concave vs. convex meniscus form?

Answer 19

a concave meniscus forms when adhesion>cohesion

Question 20

what do you know from the following information: a block is fully submerged 3 inches below the surface of a fluid, but is not experiencing any acceleration?

Answer 20

• the densities of the two substances are equal
• the volume of the block and the displaced fluid are the same
• the buoyant force equals the weight of the block and is equal to the weight of the displaced fluid

Question 21

the resistance of a fluid to flow is ____

Answer 21

viscosity

Question 22

increased viscosity increases ____

Answer 22

viscous drag

nonconservative force

Question 23

more viscous fluids ____ more energy while flowing

Answer 23

lose

Question 24

SI unit for viscosity

Answer 24

(Pa)(s)

Question 25

laminar flow

Answer 25

smooth and orderly

Question 26

the layer of fluid closer to the wall of a pipe flows ____ than more interior layers of fluid

Answer 26

more slowly

Question 27

turbulent flow

Answer 27

rough and disorderly

Question 28

in unobstructed fluid flow, turbulence can arise when the speed of the fluid exceeds a certain _____

Answer 28

critical speed

Question 29

when critical speed is exceeded, where does laminar flow occur?

Answer 29

close to wall, called the boundary layer

Question 30

boundary layer

Answer 30

when critical speed is exceeded, it is where laminar flow occurs

Question 31

____ is constant for a closed system and independent of changes in cross-sectional area

Answer 31

flow rate

Question 32

what does the continuity equation tell us?

Answer 32

that fluids will flow more quickly through narrow passages and more slowly through wider ones.

Question 33

energy density

Answer 33

similar to pressure: energy per cubic meter

Question 34

pitot tube

Answer 34

specialized measurement devices that determine the speed of fluid flow by determining the difference between the static and dynamic pressure of the fluid at given points along the tube measures static pressure during flow to calculate speed

Question 35

explain the venturi effect

Answer 35

fluid flows faster through smaller radius, the pgh term remains constant because it averages out, so therefore the static pressure at the faster moving location is less.

Question 36

what makes the circulatory system challenging for flow?

Answer 36

- nonconstant flow rate: gravity, valves, elasticity of our vessels - loss of volume into lymphatic ducts

Question 37

as blood flows away from the heart, each vessel has a _____ resistance, except when you reach the ______. because _____

Answer 37

higher capillaries resistors in parallel

Question 38

compare the volume of blood in venous and arterial circulation

Answer 38

more blood in veinous circulation

Question 39

can the continuity equation be applied to human circulation?

Answer 39

no, nonconstant flow rate

Question 40

how does total resistance change when air is breathed in

Answer 40

decreases because there are more pathways in parallel

Question 41

decreasing speed of fluid will ____ its pressure

Answer 41

increase

Question 42

what is the density from in the gauge pressure equation?

Answer 42

density of the fluid!

Question 43

does blood flow faster through the aorta or capillaries?

Answer 43

aorta because of the summation of the cross sectional area of the capillaries.