What is SCIENCE? Introduction to science as a field of study

What is Science? Science is what scientists do Science is what scientists do Science is trying to explain the world around us Science is trying to explain the world around us Science is a way of thinking Science is a way of thinking “Science is a system of knowledge based on facts or principles “Science is a system of knowledge based on facts or principles Book talks about “social science” Book talks about “social science” We prefer social studies We prefer social studies

Biological Science Earth Science Physical Science Branches of Science Science

Biological Science Earth Science Physical Science Branches of Science Science of living things Science Zoology Botany Ecology

Biological Science Earth Science Physical Science Branches of Science Science of matter and energy Science Chemistry Physics

Astronomy Meteorology Biological Science Earth Science Physical Science Branches of Science The systems of the earth Science Geology

Branches of Science There are many more branches to biological and earth sciences There are many more branches to biological and earth sciences The three categories overlap The three categories overlap Biochemistry Biochemistry Astrobiology Astrobiology Geophysics Geophysics

Science and Technology Pure Science - search for scientific knowledge Pure Science - search for scientific knowledge Technology – application of science Technology – application of science Two are interrelated Two are interrelated Technology develops new tools for investigating nature Technology develops new tools for investigating nature New science leads to new applications New science leads to new applications

Scientific Theory A reasoned explanation tested by many observations and experiments A reasoned explanation tested by many observations and experiments Tells why things are Tells why things are Three things Three things – Must explain clearly and simply – Must be repeatable – Must be able to make predictions Theories can be changed or modified by new evidence Theories can be changed or modified by new evidence

Scientific Laws Describe what happens Describe what happens Quantitative – use numbers and equations to describe Quantitative – use numbers and equations to describe Often equations are part of the law Often equations are part of the law Mathematics is a universal language Mathematics is a universal language

Law vs. Theory LawTheory Describes howExplains why Summarizes observations Agrees with observations Usually an equation Predicts new discoveries

Observations Qualitative – describe with words Qualitative – describe with words – Hot, red, large Quantitative – describe with numbers Quantitative – describe with numbers – 100°, 10 meters, 3.46 grams Scientists prefer quantitative Scientists prefer quantitative Easy to agree upon Easy to agree upon No personal bias No personal bias

Models A representation of some object or event A representation of some object or event Made to better understand it Made to better understand it Often used if real thing is too big, small or complex. Often used if real thing is too big, small or complex. Come in a variety of forms Come in a variety of forms – Physical models – Diagrams – Computer models

The Scientific Method A way of thinking about and solving problems A way of thinking about and solving problems It is a logical method It is a logical method You do it all the time You do it all the time

The Scientific Method Starts with observation- can be anything Starts with observation- can be anything Question – what do you want to know? Question – what do you want to know? Gather data- what is already known Gather data- what is already known Form hypothesis- a possible explanation based on observations Form hypothesis- a possible explanation based on observations Design experiment to test hypothesis Design experiment to test hypothesis – This is the hard part

The Scientific Method Experiments generate more observations Experiments generate more observations Allow us to draw conclusions about hypothesis Allow us to draw conclusions about hypothesis – Support the hypothesis or not – If not modify hypothesis

The Scientific Method Observe Collect data Form hypothesis Experiment tests hypothesis Observation Formulate a question Draw Conclusions

The Scientific Method Does not always work this way, but gives a way of guiding our thinking Does not always work this way, but gives a way of guiding our thinking Hard part is testing only one variable at a time Hard part is testing only one variable at a time Changing only one thing at a time allows scientists to see the effects clearly Changing only one thing at a time allows scientists to see the effects clearly If you change more than one, you don’t know which one is the cause If you change more than one, you don’t know which one is the cause

Experimental Design When experimenting, scientist focus on one factor to test two variables: When experimenting, scientist focus on one factor to test two variables: Dependent- the variable that responds as an effect of tested factors; usually on the y-axis Dependent- the variable that responds as an effect of tested factors; usually on the y-axis Independent- the variable that is manipulated or monitored to get a measurable outcome; usually on the x- axis Independent- the variable that is manipulated or monitored to get a measurable outcome; usually on the x- axis

Experimental Design Experiments involve two major groups Experiments involve two major groups Experimental Group- manipulating variables in the group to see the effect on the test subject Experimental Group- manipulating variables in the group to see the effect on the test subject Control Group- group is treated with similar conditions as the experimental group, but tested factors are left out to use as a comparison to what was being tested Control Group- group is treated with similar conditions as the experimental group, but tested factors are left out to use as a comparison to what was being tested

Measurement A number without a unit is meaningless A number without a unit is meaningless It is 4 long It is 4 long 4 what? 4 what? Scientists use the metric system or SI for le System Internationale d’Units Scientists use the metric system or SI for le System Internationale d’Units Makes sharing data easier Makes sharing data easier

Metric System Measurements have two parts Measurements have two parts Base unit and prefix Base unit and prefix Prefixes multiply or divide the base units by multiples 10 Prefixes multiply or divide the base units by multiples 10 Prefixes are the same for all units Prefixes are the same for all units

Base Units QuantityUnitAbbreviation Lengthmeterm Massgramg Temperaturekelvin L Electric current ampere K Amount of substancemolemol Volume of an objectliters A

Prefixes PrefixSymbolMeaningAs a number kilo-kthousand1,000 mega-Mmillion1,000,000 giga-Gbillion1,000,000,000 deci-dtenth0.1 centi-chundredth0.01 milli-mthousandth0.001 micro-  millionth

Metric conversions Changing the unit Changing the unit Does not change the size of the measurement Does not change the size of the measurement If the unit gets bigger the number gets smaller If the unit gets bigger the number gets smaller If the unit gets smaller the number gets bigger If the unit gets smaller the number gets bigger Math with multiples of 10 Math with multiples of 10 We will cancel out units to make sure we set the problem up right We will cancel out units to make sure we set the problem up right

Metric conversions A common race is the 5 K, which is 5 km. How many meters is this? A common race is the 5 K, which is 5 km. How many meters is this? Given unit -km Given unit -km Unit wanted –m Unit wanted –m The unit gets smaller, so the number must get bigger The unit gets smaller, so the number must get bigger 1000 m = 1 km 1000 m = 1 km

Metric conversions Distance in m = 5 km Distance in m = 5000 m 1000 m 1 km x

Metric conversions The recommended daily requirement of vitamin C is 500 mg. How many grams is this? The recommended daily requirement of vitamin C is 500 mg. How many grams is this? mass in g = 500 mg mass in g = 0.5 m 1 g 1000 mg x

Measuring length Use a ruler Use a ruler Line up from zero not the end of the ruler Line up from zero not the end of the ruler Small divisions are millimeters Small divisions are millimeters Measures in centimeters cm Measures in centimeters cm 01234

Volume Liter a common unit Liter a common unit 1 L about 1/4 of a gallon - a quart 1 L about 1/4 of a gallon - a quart 1 mL is about 20 drops of water or 1 sugar cube 1 mL is about 20 drops of water or 1 sugar cube

Measuring Volume Use a graduated cylinder. Use a graduated cylinder. The water will curve in the cylinder. The water will curve in the cylinder. Hold it level with your eye. Hold it level with your eye. Read the bottom of the curve. 15mL Read the bottom of the curve. 15mL Measures in milliliters mL. Measures in milliliters mL

Mass weight is a force, mass is the amount of matter an object is made of. weight is a force, mass is the amount of matter an object is made of. 1gram is defined as the mass of 1 cm 3 of water at 4 ºC. 1gram is defined as the mass of 1 cm 3 of water at 4 ºC. 1 kg = 1 L of water 1 kg = 1 L of water 1 kg = 2.2 lbs 1 kg = 2.2 lbs 1 g = 1 paper clip 1 g = 1 paper clip 1 mg = 10 grains of salt or 2 drops of water. 1 mg = 10 grains of salt or 2 drops of water.

Measuring Mass Use a triple beam balance Use a triple beam balance First balance it at zero. First balance it at zero. Then put item on Then put item on Then move one weight at a time Then move one weight at a time When balanced, add up the weights When balanced, add up the weights

Graphs Give a visual representation of data Give a visual representation of data Summarizes data. Summarizes data. Two types of variables Two types of variables – Independent variable the thing you have control over – Dependent variable the thing that you don’t have control over. Three types of graphs line, bar, and circle Three types of graphs line, bar, and circle

Circle Graphs Often called a pie chart Often called a pie chart divided into parts divided into parts easy to compare to whole amount. easy to compare to whole amount. Use several to show changes over time Use several to show changes over time

Bar Graphs Bar Graphs Bar Graphs- wide columns used things like weight, height, and length. Bar Graphs- wide columns used things like weight, height, and length. Compare quantities Compare quantities

Line Graphs Line Graphs- compares sets of data, show change and patterns over time. Line Graphs- compares sets of data, show change and patterns over time.

Graphs include A title A title Labeled axes Labeled axes A consistent scale. A consistent scale.

Scientific Reasoning You have been a scientist your entire life! You have been a scientist your entire life! If you have ever figured out how something works, fixed something that was broken without instructions, or solved a problem using your mind then you have used scientific reasoning. If you have ever figured out how something works, fixed something that was broken without instructions, or solved a problem using your mind then you have used scientific reasoning. Think like a scientist to have success in this class and in life. Think like a scientist to have success in this class and in life.

Review Quiz What is science? What is science? Describe the 3 branches of science? Describe the 3 branches of science? Compare the difference between a scientific law and scientific theory? Compare the difference between a scientific law and scientific theory? Which type of observation relies on measurable units? Which type of observation relies on measurable units? Why do scientists use models? Why do scientists use models? List the steps of the scientific method? List the steps of the scientific method? Why is the metric system used by scientists? Why is the metric system used by scientists?

Review Quiz Which tools are used to measure distance, volume, and mass? Which tools are used to measure distance, volume, and mass? Which units are used to measure distance, volume, and mass? Which units are used to measure distance, volume, and mass? List the 3 types of graphs and tell a scenario for how you would use each? List the 3 types of graphs and tell a scenario for how you would use each?