Scientific Method and the Metric System

Science as a Process Steps of the Scientific Method Involves making observations, asking questions, forming hypotheses, making predictions, designing experiments, analyzing data, and drawing conclusions

Scientific Method Steps Step 1: State Problem or Question Observation – using all senses to gather information Inference – assumption based on observation

Scientific Method Steps Step 2: Gather information Accuracy (correct ) vs. Precision (closeness of measurements together) Quantitative (1 cm, 45 kg, etc.) vs. Qualitative (cloudy, fuzzy, blue, etc.) Step 3: Form Hypothesis Hypothesis - proposed explanation for the way a particular aspect of the natural world functions. If … Then Statement If he studies his biology notes every night, then he will pass the biology Keystone exam.

Scientific Method Steps Step 4: Test Hypothesis Performing the Experiment A controlled experiment compares an experimental group and a control group and only has one variable. 1. Control group - provides a normal standard against which the biologist can compare results of the experimental group. 2. Experimental group is identical to the control group except for one factor. Independent variable – intentionally changed Dependent variable - affected by the independent variable Experiment should be repeated and completed without bias

Scientific Method Steps Step 5: State Conclusion Hypothesis must be accepted or rejected through data from experiment When writing conclusion: Hypothesis must be stated Include data that accepts/rejects hypothesis Step 6: Share Results Publish results in scientific journal to share with community

Quick Review List the steps of the scientific method in the correct order. 1. _____________________________________________________ 2. _____________________________________________________ 3. _____________________________________________________ 4. _____________________________________________________ 5. _____________________________________________________ 6. _____________________________________________________

Theory vs. Law Theory - set of related hypotheses confirmed to be true many times, and it can explain a great amount of data Law – general statement that describes a wide variety of phenomena under specific set conditions

Units of Measurement Base and Other Units Scientists use a single, standard system of measurement, called the metric system King Henry (KHDSDCM) – use for conversions Kilo (k) Hecto (h) Deca (da) Standard (m,l,g) Deci (d) Centi (c) Milli (m) Ex. 18m = 1800cm Ex. 2.4dag = 0.024kg

Quick Review Using King Henry complete the following conversions: 12 g = ______________ cg .75 dL = ____________ daL 1346 hm = ____________ m

Units of Measurement Base and Other Units Metric system has seven base units Commonly used ones for this course: Meter (m) – distance Liter (L) – liquid measurement Gram (g) - weight