Intro unit: Nature of Science Science is organized common sense Science is organized common sense Hypothesis: An educated guess, based upon prior knowledge/experiences Hypothesis: An educated guess, based upon prior knowledge/experiences

Inference: Inference: logical explanation logical explanation of an event based of an event based on observable on observable characteristics characteristics (even without all (even without all of the information) of the information)

Controlled Variables – variables kept constant so as to not affect results Controlled Variables – variables kept constant so as to not affect results ex: same plants, same soil, same temp. same light, etc. Independent (Manipulated) Variable – variable changed on purpose (it’s the factor being tested) Independent (Manipulated) Variable – variable changed on purpose (it’s the factor being tested) ex. plant 1= 100ml H 2 0, plant 2=50ml H 2 O, plant 3=10ml H 2 O Dependent (Responding) Variable – the results. It’s what happens as a result of the manipulated variable Dependent (Responding) Variable – the results. It’s what happens as a result of the manipulated variable ex. plant 1 grew 4 inches, plant 2 grew 2 inches, plant 3 died [You can never have more than 1 independent variable, or you would not know which variable caused the results.] [You can never have more than 1 independent variable, or you would not know which variable caused the results.]

Data: Information gathered through observation. Data: Information gathered through observation. Qualitative data uses the senses Qualitative data uses the senses ex. table is smooth, black, hard, rectangle, etc. Quantitative data uses measurements Quantitative data uses measurements ex. table top is 150 cm long and 30 cm wide

Steps in the Problem Solving Method: State the Problem: State the Problem: {what are you trying to find out?} State the Hypothesis State the Hypothesis {what do you think will happen? Why?} {what do you think will happen? Why?} Test the Hypothesis {list materials & directions to use those materials.} Record & Analyze Data Record & Analyze Data {quantitative, or quantitative data; data tables, or graphs} Draw Conclusions Draw Conclusions {multiple sentences: What did you learn, confirm, etc. Identify factors affecting the results, major concepts, questions the experiment generated, etc.} questions the experiment generated, etc.}

Graphs & Tables – used to collect and analyze data (a picture of the results). Independent variable goes on the X-axis. Dependent variable goes on the Y-axis. Always give a graph a descriptive title, and completely and accurately label the X & Y axis. Line graph shows change over time. change over time. Bar graph compares amounts

Circle graph (pie chart) shows the parts compared to the whole.

Theory – a well tested explanation that explains a phenomena, based on many observations over a number of years (ex: Big Bang Theory) Theory – a well tested explanation that explains a phenomena, based on many observations over a number of years (ex: Big Bang Theory) Scientific Law – a tested and proven fact of nature. It happens that way every time. (Ex: Law of Gravity) Scientific Law – a tested and proven fact of nature. It happens that way every time. (Ex: Law of Gravity) Scientific Model –a representation used to explain a concept that may be to small, large, far way, dangerous, etc. to be studied otherwise. Scientific Model –a representation used to explain a concept that may be to small, large, far way, dangerous, etc. to be studied otherwise. (3-D model, picture, diagram, equation, etc.)

Scientific Notation - a type of shorthand in which a number is expressed as a value between 1 and 10 multiplied by a power of 10. Scientific Notation - a type of shorthand in which a number is expressed as a value between 1 and 10 multiplied by a power of 10.Examples: 4 x is 4,000,000,000,000,000,000, x is 3,141,000,000,000,000,000

Primary Scientific Measurements Length or Distance: Meter Stick, meters; Length or Distance: Meter Stick, meters; m, cm, mm m, cm, mm Mass: Balance Scale, grams; g or kg Mass: Balance Scale, grams; g or kg Volume: Beaker or Graduated Cylinder; liters; L or mL Volume: Beaker or Graduated Cylinder; liters; L or mL Temperature: Thermometer, degrees celsius; ºC Temperature: Thermometer, degrees celsius; ºC Time: Clock, Calendar; min., s, hr, day, etc. Time: Clock, Calendar; min., s, hr, day, etc.

Sometimes 2 types of measurement are combined. Examples: Density: mass/volume 10 g/2 ml = 5 g/ml Speed: distance/time 10 m/5 s = 2 m/s

Metric System Scientific measurements are made in metrics for the following reasons: Scientific measurements are made in metrics for the following reasons: 1. Recognized world wide 2. More accurate 3. Easier because it’s based on 10 (just moved decimals to convert)

Metric Prefixes milli- m0.001 milli- m0.001 centi-c0.01 centi-c0.01 deci- d0.1 deci- d0.1 Deka- dk 10 Deka- dk 10 Hecto- h 100 Hecto- h 100 Kilo- k 1000 Kilo- k 1000 To convert from a smaller to a larger unit, move the decimal to the left equal to the number of zeros. To convert from a smaller to a larger unit, move the decimal to the left equal to the number of zeros. To convert from a larger to a smaller unit, move the decimal to the right equal to the number of zeros. To convert from a larger to a smaller unit, move the decimal to the right equal to the number of zeros.