theory,law,fact
Post on 26-Feb-2016
38 Views
Preview:
DESCRIPTION
TRANSCRIPT
THEORY,LAW,FACT
WHAT IS THE BASIC
ASSUMPTION OF SCIENCE?
Nature is OrderlyWith this assumption we can explain
phenomenon using scientific theories
SPEC
UL
ATIO
N
A speculation is a general statem
ent about nature that is constructed without fact (or enough fact)
Scientific speculation is a legitim
ate part of the scientific process that develops early ideas that are not yet robust enough to be a testable, falsifiable or worthy of being a m
ore formal
"hypothesis".
QU
ESTIO
NS
: What m
akes up a theory?
What is Speculation?
What is the difference between
a scientific law and a scientific fact?
What theories/facts/laws do you
know?
SCI
ENT
IFIC
FAC
T Amazing facts: D
id you know that
there are 206 bones in the adult hum
an body and there are 300 in children (as they grow
some of the
bones fuse together).
The longest living cells in the body are brain cells w
hich can live an entire lifetim
e.
The cosmos contains approxim
ately 50,000,000,000 galaxies.
There are between 100,000,000,000
and 1,000,000,000,000 stars in a norm
al galaxy.
Hydrofluoric acid w
ill dissolve glass
A fact is an objective,verifiable observation.It is the same everywhere.It can and has been,verified many times.
It is a statement intended to
explain a phenomenon.
How certain is a theory?
Many people say it’s a guess or
speculation, which is how standard English uses the word Theory
When a scientist speaks about a
theory it means som
ething com
pletely different:
HOW WOULD YOU DEFINE THEORY?
Scientific Theory:
An explanation of how
and why a
natural phenomenon behaves the
way it does that is confirm
ed by all available evidence such that it could be used to predict new
,as yet unobserved phenom
ena
SCI
ENT
IFIC
THE
ORY
Examples of Scientific Theory:
The theory of relativity: that the laws of physics are the sam
e for all observers
The theory of evolution by natural selection: that the observed changes in species occur due to non-random
selection of well adapted specim
ens over less well adapted specim
ens
The Big Bang Theory:that the universe began as an infinitely sm
all point that underwent expansion to form
the universe as we know it today.
AR
E THE FO
LLOW
ING
TH
EOR
IES OR
FAC
TS?
Some illnesses are caused by
microscopic organism
s. The germ
theory of illness.
That the planets in our solar system
orbit around the sun. The heliocentric solar system
.
That the Earth is round, and not flat, or som
e other shape. The round earth theory
That all matter is m
ade up of atoms.
The atomic theory of m
atter
Why are these “facts” still
considered theories?
They are indeed facts, but they still fit into
the definition of theory because they
intend to explain
HO
W
DO
YO
U
FOR
M A
THE
ORY
?
THE
ORYF
ACT
Most theories cannot ever
be transformed into fact.
A theory is a
general statem
ent intended to explain facts
EVOLU
TIO
N
The theory of evolution by natural selection
Evolutionfact
Scientists considered evolution a fact before Darwin proposed his theory of natural selection.
SCI
ENT
IFIC
LAW
A law is similar to a theory in that it can be used to make predictions, but is less general and tends to be more mathematical in nature.
EXAM
PLES O
F SC
IEN
TIFIC
LAWS: N
ewton’s Law
s of motion:
statements about how large
objects made of atom
s behave when m
oving at low speeds relative to each other.
The Laws of Therm
odynamics:
statements about entropy,
temperature, and therm
al equilibrium
.
Law of G
ravity: Every particle attracts every other particle with a force that is proportional to the product of their m
asses and inversely proportional to the distance between them
.
LAWS M
AY BE PR
OVEN
FA
LSE, SO W
HY D
O W
E K
EEP THEM
?Newton’s laws of m
otion break down when the objects are very sm
all or moving very fast
relative to other objects. Why
do we keep them?
Because in everyday world situations they are very good at predicting. Engineers use them
for designing sky scrapers and travel through space is possible because of them
even though they are not always correct.
Remem
ber also that most
laws have never been
proven to be false!
SUM
MA
RY:
A theory is constructed most of
all from facts.
Theories contain laws, but laws m
ean very little without facts.
Theories also contain logical inferences that talk about how we know what we know.
Accumulating all of these, the
scientist makes a general
statement to explain all the
evidence. Other scientists reaffi
rm the facts and use the
theory to make predictions and
obtain new facts.
top related