Modelling

Question 1

what are the means to understand if something works

Answer 1

Modeling, Prediction, Scaling

Question 2

Laws of engineering

Law 1:

Law 2:

Law 3:

Law 4:

Law 5:

Law 6:

Law 7 :

Answer 2

Law 1: Big machines are more efficient than small machines

Law 2: For a long production (high volume) cost of product approaches cost of materials (that is, R&D and manufacturing cost become insignificant)

Law 3: No measurement is more accurate than six significant figures (and the sixth is very expensive)

Law 4: Moore’s Law (MIPS = 2^ (YEAR-1984))

Law 5: Engineering laws are local; fit a particular time and context

Law 6: Murphy’s Law

Law 7 : Half of everything you hear in a classroom is crap. Education is figuring out which half is which.

Question 3

what are our conceptual models based on

Answer 3

fragmentary/poor information that might be accurate or inaccurate.

Question 4

Thus many of our conceptual models are what?

Answer 4

to a greater or lesser extent, flawed

Question 5

If the Froude number is the same for a ship and its model

Answer 5

both will behave the same way

Question 6

Fr =

Answer 6

V^2/Lg

Question 7

If the Mach number is the same for an airplane and its model

Answer 7

both will be in the same sonic regime

Question 8

M=

Answer 8

v/c

Question 9

At a critical value of Reynolds number

Answer 9

flow changes from laminar to turbulent

Question 10

Re=

Answer 10

ρvl/μ

inertial Forces/Viscous Forces

Question 11

ReD < 2300

Answer 11

laminar flow

Question 12

ReD > 2900

Answer 12

turbulent flow

Question 13

Weber NumberIndicates what

Answer 13

the ratio between inertial forces and surface tension forces

Question 14

We =

Answer 14

ρV2l/σ

Question 15

what is fuzzy logic

Answer 15

models of systems that are deliberately imprecise

Question 16

clouds that cover the tree of knowledge

Answer 16

1. incpmputability
2. chaos
3. quantum physics