Download Models - TeacherWeb

Bell work
 Answer
the following questions:
 How is an airplane flight simulator a
kind of model?
 What are some advantages to
training pilots in a flight simulator
rather than in a real airplane?
 Write
your answers in your science
journal-composition book.
Models
What do you think a
model is?
Objectives for Today!
• Give examples of three types of models.
• Identify the benefits and limitations of models.
• Compare the ways that scientists use hypotheses,
theories, and laws.
What is a Model

A model is a representation of an object
or system.
– Models often use familiar objects or ideas that
stand for other things.
Greeks were the first people known to
make models of nature.
 They used logic and geometry to explain
patterns in nature without resorting to
myth or the supernatural.
 They sought to understand the
architecture of the Universe by
constructing models of nature.

What is a Model
 Keep
in mind that models have
limitations.
– A limitation is how the model is not
perfect.
 Models
are often used to represent
things that are very small or very
large. Particles of matter are too
small to see.
 Three major kinds of scientific
models are physical, mathematical,
and conceptual models.
What do you think a…
 Physical
model is?
 Mathematical model is?
 Conceptual model is?
Objectives for Today!
• Give examples of three types of models.
• Identify the benefits and limitations of models.
• Compare the ways that scientists use hypotheses,
theories, and laws.
Physical Models
 Model
airplanes, maps, and dolls are
physical models.
 Physical models of systems that can
be easily observed and manipulated.
 Have characteristics similar to key
features of more complex systems in
the real world.
 A limitation of a doll as the model of
a baby is that the doll doesn't act
like a baby.
Give an example of a physical model.
 What are some limitations?

Physical models
Mathematical Model

A mathematical model is made up of
mathematical equations and data.
– Simple mathematical models allow you to calculate things
such as how far a car will go in an hour.
– Other models are so complex that only computers can
handle them.
Involve solving relevant equation (s) of a
system or characterizing a system based
upon its statistical parameters such as
mean, mode, variance or regression
coefficients.
 Using the most correct data does not make
the prediction correct, this is a limitation.
 A change in a variable that was not
predicted could cause the model to fail.
 Give an example of a mathematical model.

Mathematical Model: A Punnett Square
• The Punnett
square helps
scientists
study the
passing of
traits from
parents to
offspring.
Projected Population Estimates
2005
5 year
increments
2010
.
Africa
Asia
Europe*
N.A.
891
3,913
729
512
S.A.
O.
+Aus.
Total
371
32
6.45
Nat.
Geo.
6.8
2011
7.00
2012
7B
7.05
1 year
increments
2013
7.10
2014
7.15
2015
7.2
2020
7.6
2025
1,327
4,753
711
618
447
39
2030
2035
7.89
8.2
5 year
increments
8.5
2040
8.8
2045
9.4
9B
10.5 B
2050
.
Estimated 2050
Pop. Distribution
2,050
6,109
458*
720
475
43
9.85
20.8%
62.0%
4.6%
7.3%
4.8%
0.4%
99%
* The data for Europe includes all of Russsia, except for 2050.
-
Conceptual Model
The third kind of model is a conceptual
model.
 Some conceptual models are systems of
ideas.
 Others are based on making comparisons
with familiar things to help illustrate or
explain an idea.

– One example of a conceptual model is the
system that scientists use to classify living
things. By using a system of ideas, scientists
can group living things by what they have in
common. This type of model allows scientists
to better understand each group of living
things.
Conceptual Model
 People
receive information, process
this information, and respond
accordingly many times each day.
 This sort of processing of information
is essentially a conceptual model (or
mental model) of how things in our
surrounding environment work.
 Give an example of a Conceptual
model.
Conceptual models
Universe-everything
–Galaxies-
billions of
stars grouped together
Systems-
1 star
and it’s orbiting bodies
–Planet
–Comets
–Asteroids
Objectives for Today!
• Give examples of three types of models.
• Identify the benefits and limitations of models.
• Compare the ways that scientists use hypotheses,
theories, and laws.
What do you think a…
 Theory
 Law
is?
is?
What is a Theory?




Models are often used to help illustrate and
explain scientific theories.
A theory is a unifying explanation for a range of
hypotheses and observations that have been
supported by testing. (Definition copy as is!)
A theory not only can explain an observation
you've made but also can predict what might
happen in the future.
Keep in mind that models can be changed or
replaced.
– These changes happen because new observations cause
scientists to change their theories.
Can you think of a theory you
have heard of?
 Big
Bang
 Relativity
 Worm holes
 Why
are these theories?
What is a Law?
What happens when a theory and its
models correctly predict the results of
many different experiments? A scientific
law could be formed.
 A law is a summary of many experimental
results and observations.
 A law tells you how things work.
 A law tells you to expect the same thing to
happen every time.

Can you think of a Scientific
law?
 Law
of gravity
 Law of Conservation of Energy
 Laws of motion
 Why
are these laws and not
theories?
Objectives for Today!
• Give examples of three types of models.
• Identify the benefits and limitations of models.
• Compare the ways that scientists use hypotheses,
theories, and laws.