Just What Is Science Anyway???

a journey through the scientific method...

Science is a process of inquiry - asking questions and

getting answers you do science there are many sciences

life science poli-science social science etc

Observation before you can ask a question - you need to

make an observation…

2 kinds Direct observation- done w/ the 5 senses

sight, touch, smell, aural, taste Indirect observation - done w/ equipment

thermometer, anemometer, balance...

The Scientific Method a very good way to do science easy to follow repeatable thorough is the way it’s really done in the field! (BUT NOT THE ONLY WAY!)

What’s the Purpose?? you need to state the goal of your

investigation - called the Purpose (or Problem) Statement it needs to be clear to you (and the reader)

exactly what you are investigating

The “magic” purpose statement

The purpose of this experiment is to determine the effect of ______(iv)_______ on the _______(dv)_______.

Procedure you need to list the steps that you are going

to (or did) take to carry out your experiment it must be so detailed so that anyone who

may dispute your work can reproduce exactly what you did

The Rope Problem!!!

Variables to vary - to change Independent (manipulated) Variable (IV) -

the part of the experiment that you change Dependent (responding) Variable (DV) -

the part of the experiment that changes as a result of changing the independent variable (the outcome)

more... Controlled Variables - the parts of your

experiment that do not change WHY have these?

Control Group - the part of the experiment that is your basis for comparison (you don’t do anything to this group)

An Hypothesis….. ..is an educated prediction - “educated”

implies that the predictions are based on research and your prior experiences.

Should be stated in “If... Then… statements Ex:“If a car’s mass is increased then it will

go faster down a ramp.”

Paper Towel Lab

Come up with an agreed general procedure

Procedure/variables might get altered Keep all other variables constant!!!

No out of control experimentation!) EVERYONE takes notes in lab group! Make sure you use measuring tools

properly. (accuracy counts in grade)

Data Presentation data tables

a simple way to organize your data graphs

to help your data make visual sense trends

Mass of cart (g)

Ramp angle (deg)

Ramp length (cm)

Time (s)

Ave. time (s)

40.00 45.0 35.0 11.30

40.00 45.0 35.0 12.10 11.70

25.00 45.0 35.0 10.90

25.00 45.0 35.0 11.90 11.40

Data table

Table 1: Cart speed based on cart Table 1: Cart speed based on cart massmass

Mass of cart (g)

Ramp angle (deg)

Ramp length (cm)

Time (s)

Ave. time (s)

40.00 45.0 35.0 11.30

40.00 45.0 35.0 12.10 11.70

25.00 45.0 35.0 10.90

25.00 45.0 35.0 11.90 11.40

Table 1: Cart speed based on cart Table 1: Cart speed based on cart massmass

Units of measure

Mass of cart (g)

Ramp angle (deg)

Ramp length (cm)

Time (s)

Ave. time (s)

40.0 45.0 35.0 11.30

40.0 45.0 35.0 12.10 11.70

25.0 45.0 35.0 10.90

25.0 45.0 35.0 11.90 11.40

Table 1: Cart speed based on cart Table 1: Cart speed based on cart massmass

Significant digits

Significant digits...

…are a way to show how accurate the measurements are

(depends instrument is being used) Example: Triple beam balance

measures to the nearest tenth of a gram, therefore all mass measurements should only go out one decimal point

Mass of cart (g)

Ramp angle (deg)

Ramp length (cm)

Time (s)

Ave. time (s)

40.0 45.0 35.0 11.30

40.0 45.0 35.0 12.10 11.70

25.0 45.0 35.0 10.90

25.0 45.0 35.0 11.90 11.40

Table 1: Cart speed based on cart Table 1: Cart speed based on cart massmass

Highlight important stuff

Mass of cart (g)

Ramp angle (deg)

Ramp length (cm)

Time (s)

Ave. time (s)

40.0 45.0 35.0 11.30

40.0 45.0 35.0 12.10 11.70

25.0 45.0 35.0 10.90

25.0 45.0 35.0 11.90 11.40

Table 1: Cart speed based on cart Table 1: Cart speed based on cart massmass

Give it a clear title

Conclusions INTERPRET THE DATA:

what do all of these numbers mean?

do they answer the problem statement?

why or why not?

Analyze for errors …

what factors skewed your data?how far off were the results?Look to see if any trials were

“outliers”What should be done next time

to reduce any errors?

Reflect…. What link to our studies did this lab

have? Did you learn anything new, any

surprises? Any comments or questions? Anything you might add? What happened with your hypothesis and

why was it right or wrong?

Precision vs. Accuracyif your data is accurate it is close to its true value

if your data is precise it is consistent from trial to trial

Precision vs. Accuracy

this is precise but not accurate

Precision vs. Accuracy

this is precise and accurate

Accuracy comes from________?Precision comes from________?

Answers: equipment

people

All Done...