Chapter 2Data in Science

Section 1: Tools and Models

Vocabularymass

amount of matter in an objectvolume

amount of space something occupiesmeasure of the size of an object in a 3D space

densityamount of a matter in a given volume

D = mass/volume D= m/v

Vocabularytemperature

measurement of how hot/cold substance ismodel

representation of object or a system

Vocabularytheory

a system of ideas that explains many related observations and is supported by a large body of evidence

Lawdescriptive statement or equation that reliably

predicts events under certain conditions

Tools in ScienceNeed to be accurateuse the proper tool

Making MeasurementsInternational System of Units

aka “metric system”based on multiples of 10

Making MeasurementsLength

meter (m)Mass

kilogram (kg)1 kg = 2.2 lbs

volumeliter ( L )

1 mL = 1 cm³

Densityratio of mass to volume

amount of matter inside

Models in Scienceused to simplify complex conceptsphysical

sketch or scale trainmathematical

weathereconomics

conceptualbig bang theory

Models in scienceRight size

models help to make large items easy to see

models brings to life unseen conceptssound waves

Limitationsonly as good as information put into it

Making Scientific Progress

Models:summarize infotool for communication

Making Scientific Progress

Scientific Theorybased upon repeated tests of a

hypothesisexplainsand predicts

Lawsummary of multiple experimentstells you how things workstronger than theory

Section 2: Organizing Data

Vocabularyindependent variabledependent variableaxis

Vocabularyindependent variable

the factor that is deliberately manipulateddependent variable

the factor that changes as a result of the independent variable being changed

Vocabularyaxis

one of two reference lines that mark the borders of a graph.

Dependent Variable

Independent Variable

Creating a Data Tableorganization is key

gather data from researchdata table with 2 columns

independent variable goes on x-axisfactor that is changed in an experiment

dependent variablesgoes on y axischanges as a result of the independent

variable

Creating a Data TableControlled parameter

factors that stay constant throughout the experiment

variable parameterfactors that change in an experiment

Creating a Graphhighly visual

easy format to see informationAxis

x-axis is horizontal x-axis is independent variabley-axis is verticaly-axis is dependent variable

Creating a tableRange

the extent of each variablesubtract the smallest value from the

largest value

Range:

x axis:

6 days- 1 days = 5 days

y axis

65 deg - 40 deg = 25 degrees

Creating a TableScale

each axis has its own scale factorData Points

plot data points firstthen find line of best fit

captures the most datalinear

Creating a TableLabels!

each axisand a title

Patterns Shown by Graphs

trenddirection or pattern of data

straight line = linearcurved line = non-linear

Patterns Shown by a Graph

Positive or Negative Relationship

Sec 3: Analyzing Your Data

vocabularyMeanMedianModeSlope

Vocabularymean- the number obtained by adding up the data and dividing by the sum of the occurances.

- aka… AVERAGE- median

- middle number when data arranged in order from lowest to highest

Vocabularymode- most frequently occurring value

slope- measure of the steepness of a line

- ratio of rise over run

Why Mathematics?• Math is international language• measures properties• exact• patterns can be seen

Accuracy of Data• make sure tools are functioning

correct• make sure you are using tool

properly

Reproducing Data• data must be reproducible in

future experiments • verifies the results

Describing Data Sets mean

average find the mean of

26, 20, 15, 27

Describing Data Set median

the middle number

Describing Data SetMode

➔number that appears most often

Slope of a Line➔rate of change ➔slant of a line

◆rise over run◆change of y values divided by the change

of x values

Slope of a Line Positive, Negative, or horizontal lines