Chapter 1

Question 1

Name some physical parameters that can be used to describe a flow.

Answer 1

1. Size or characteristic length
2. Speed, V
3. Pressure, P

Question 2

Define a fluid.

Answer 2

A fluid is a substance that deforms continuously when acted on by a shearing stress of any magnitude.

Question 3

Describe the difference between qualitatively and quantitatively with respect to fluid mechanics.

Answer 3

Qualitative: Nature or type of characteristics of the flow. (e.g. Length, time, stress, and velocity)
Quantitative: Provides numerical values to the qualitative.

Question 4

The qualitative description requires both

Answer 4

A number and a standard or unit.

Question 5

Definition of a pound with respect to a slug.

Answer 5

1 lb = (1 slug)(1 ft/s^2)

Question 6

1 slug is how many pounds (lbm)?

Answer 6

32.2lb

Question 7

What is specific volume?

Answer 7

v = 1/rho where rho is the density.

Question 8

What are the BG and SI units for specific weight?

Answer 8

BG: lb/ft^3
SI: N/m^3

Question 9

Give the definition of a Newtonian fluid.

Answer 9

Fluids for which the shearing stress is linearly related to the rate of shearing strain (also referred to as the rate of angular deformation).

Question 10

Give the definition of a Non-Newtonian fluid.

Answer 10

Fluids for which the shearing stress is NOT linearly related to the rate of shearing strain.

Question 11

Give the BG and SI units for viscosity.

Answer 11

BG: lbs / ft^2
SI: Ns / m^2

Question 12

What is the conversion equation between Rankine and Fahrenheit?

Answer 12

R = F + 459.67

Ref: Pg 7

Question 13

What is the gravitational acceleration in the BG system?

Answer 13

32.2 feet / second^2

Ref: Pg 8

Question 14

What is the ideal gas equation?

Answer 14

absolute pressure = (density)(the gas constant)(absolute temp)

Ref: Pg 12

Question 15

True or False

In the ideal gas law, you can use the gauge pressure.

Answer 15

False, absolute pressures must be used.

Ref: Pg 12

Question 16

What is the relationship between applied force on a body immersed in fluid and shearing stress?

Answer 16

Force = (tao)(area)

Ref: Pg 14

Question 17

What is the no-slip condition?

Answer 17

A statement of a fluid’s viscosity, which says that the velocity of a fluid is zero at the interface of a solid boundary.

Ref: Pg 14

Question 18

What is the equation for the rate of shearing strain?

Answer 18

gamma_dot = du/dy

Ref: Pg 15

Question 19

True or False

The absolute viscosity is the same thing as the dynamic viscosity?

Answer 19

True

Ref: Pg 15

Question 20

What is the relationship between shear stress and viscosity?

Answer 20

Shear stress = (viscosity)(shearing strain)
or;
(Tao) = (Mu)(du/dy)

Ref: Pg 15

Question 21

For shear-thinning fluids ____.

Answer 21

The apparent viscosity decreases with increasing shear rate. In other words, the harder the fluid is sheared the less viscous it becomes. Latex-based paints are an example.

Ref: Pg 16

Question 22

For shear-thickening fluids _____.

Answer 22

The apparent viscosity increases with increasing shear rate–the harder the fluid is sheared the more viscous it becomes. An example would be water mixed with corn starch.

Ref: Pg 16

Question 23

True or False

A Bingham plastic is neither a solid nor a liquid.

Answer 23

True

Ref: Pg 16

Question 24

Give two examples of Bingham plastics.

Answer 24

Toothpaste and mayonnaise.

Ref: Pg 16