chapter 1 – science skills
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1.1 – What is Science. Chapter 1 – Science Skills. What is Science?. A system of knowledge and the methods you use to find that knowledge Observation and measuring are the means of scientific discovery The root of science is curiosity!. Measurements. Qualitative. Quantitative. - PowerPoint PPT PresentationTRANSCRIPT
Chapter 1 – Science Skills
1.1 – What is Science
What is Science?
A system of knowledge and the methods you use to find that knowledge
Observation and measuring are the means of scientific discovery
The root of science is curiosity!
Measurements
QUALITATIVE Descriptive
observations Think “QUALITY”
QUANTITATIVE Numerical
observation Think
“QUANTITY”
What is technology?
The use of knowledge to solve practical problems
What kind of technology do you use?
What practical problems does that technology solve?
Branches of Science
Three Branches of Science Physical Science Earth & Space Science Life Science
Scientific InvestigationsOBSERVATIONS Information that is
gained through your senses
INFERENCES Something that
you think might be true based on observations
Evidence-based guesses
Observations vs. Inferences Your group will be provided an
object. Make three observations and three inferences about this object.
The Scientific Method1.2 Using a Scientific Approach
What is the scientific method? It is a process that is used to find
answers to questions about the world around us.
Is there only one scientific method? No, there are several versions of the
scientific method. Some versions have more steps, while others may have only a few. However, they all begin with the identification of a problem or a question to be answered based on observation of the world around us and provide an organized method for conducting and analyzing an experiment.
What is a hypothesis?
It is an educated guess based on observations and your knowledge of the topic.
ADD TO NOTES A hypothesis is a proposed answer to a
question A hypothesis is only useful if it is
TESTABLE
What is data?
It is information gathered during an experiment.
ADD TO NOTES Observations▪ Information that is gained through your
senses
Steps of the Scientific Method
Identify the Problem
Form a Hypothesis
Create an Experiment
Perform an Experiment
Analyze the Data
Communicate the Results
Is the data inaccurate or the
experiment flawed?
Modify the Experiment
Testing a Hypothesis
Experimental Variables Any factors that can change in an
experiment
Two types of Variables Independent Variable (the manipulated
variable) Dependent Variable (the responding
variable)
Dancing with the Stars & Variables Kate Gosselin & Tony Dovolani - Jive (Start at 3:25)
Variables
INDEPENDENT
The variable that is purposefully changed in an experiment by the experimenter
A change in this variable results in a change in another variable
ALWAYS graphed on the Y-axis
DEPENDENT
The variable that is being measured in an experiment
This variable changes in response to changes in the independent variable
ALWAYS graphed on the X-axis
Example 1 If a scientist conducts an experiment to test
the theory that a vitamin could extend a person’s life-expectancy, then the independent variable is the amount of vitamin that is given to the subjects within the experiment. This is controlled by the experimenting scientist.
The dependent variable, or the variable
being affected by the independent variable in this case, is life span.
IV & DV Examples Game
Controlled Experiments
An experiment in which only one variable, the independent variable, is deliberately changed at a time.
Constants Experimental variables that must remain
consistent in order to test a hypothesis
Example 1
In an experiment designed to test the effect of water temperature on how fast sugar can be dissolved in a pitcher of Kool Aid, what variables should remain constant?
Example 2
In an experiment designed to test which dog food is preferred by dogs, what variables should remain constant?
Drawing Conclusions
Conclusions summarize the findings of an experiment
All conclusions should explicitly state whether or not the results of an experiment supported the original hypothesis
Scientific Theories
A well-tested explanation for a set of observations or experimental results
Theories are never proved, but rather become stronger if facts continue to support them
Facts are repeatable observations
Scientific Laws
A statement that summarizes an observed pattern found in nature without attempting to explain it.
The explanation of such a pattern is provided by a scientific theory
Precision & Accuracy1.3 Measurement
Scientific Notation
A way of expressing a value as the product of a number between 1 and 10 and a power of 10
Makes very large or very small numbers easier to work with
Examples 300,000,000 can be written as 3.0 x 108 0.00086 can be written as 8.6 x 10-4
Multiplication & Division
Multiply the numbers before the multiplication signs, then add the exponents of the 10
Divide the numbers before the multiplication signs, then subtract the exponents of the 10
Practice
A rectangular parking lot has a length of 1.1 x 103 meters and a width of 2.4 x 103 meters. What is the area of the parking lot?
4.5 x 103 / 9.0 x 10-1
SI Units of Measurement
All measurements must have both a number value and a unit
SI = International System of Units Units of measurement that are used in
scientific investigation Consists of both base units and derived
units
SI Base Units
SI Base UnitsQuantity Unit Symbol
Length Meter mMass Kilogram kgTemperature Kelvin KTime Second sAmount of Substance Mole molElectric Current Ampere ALuminous Intensity Candela cd
SI Derived Units
SI Derived UnitsQuantity Unit Symbol
Area Square meter m2
Volume Cubic meter m3
Density Kilograms per cubic meter
kg/m3
Pressure Pascal (kg/m•s2) PaEnergy Joule (kg•m2/s2) JFrequency Hertz (1/s) HzElectric Charge Coulomb (A•s) C
Metric Prefixes
Indicates how many times a unit should be multiplied or divided by 10
The easiest way to convert from one unit of measurement to another is to use conversion factors Conversion Factor: A ratio of equivalent
measurements that is used to convert a quantity expressed in one unit to another unit
SI Prefixes
SI PrefixesPrefi
xSymb
olMeaning Multiply
Unit Bygiga- G billion (109) 1,000,000,000mega- M million (106) 1,000,000kilo- k thousand (103) 1000deci- d tenth (10-1) 0.1centi- c hundredth (10-2) 0.01milli- m thousandth (10-3) 0.001micro- μ millionth (10-6) 0.000001nano- n billionth (10-9) 0.000000001
Conversion Factor Example Mount Everest is 8848 meters high.
Convert this number to kilometers. There are 1000 meters in 1 kilometer ▪ (1000 m/ 1 km)
Precision & Accuracy
Precision A gauge of how exact a measurement is
Accuracy The closeness of a measurement to the
actual value of what is being measured
Measuring Temperature
Three types of scales Fahrenheit Celsius Kelvin
You can convert between all three scales using the following formulas ºC = 5/9 (ºF – 32.0º) ºF = 9/5 (ºC) + 32.0º K = ºC + 273