Unit 1-Inquiry

What is the Scientific Method? O The scientific method is a process for experimentation that is used to explore observations and answer questions. O In other words, it’s a way to solve a problem.

Steps in the Scientific Method 1. Observations 2. Identify the Problem 3. Form Hypothesis 4. Experiment 5. Gather and analyze data 6. Draw Conclusion

Step 1: Observation O The act of noting or perceiving objects or events using the senses. Look, Observe, Analyze

Step 2: Identify the problem O Observations raise questions What is the problem? What are you trying to solve?

Step 3: Form a Hypothesis O an educated guess O A suggested solution to the problem. O Must be testable O Predicts an outcome O Sometimes written as If… Then… O Sometimes written as If… (IV goes here), Then… (DV goes here)

Variables Variables are things that change.

Independent Variable manipulated variable A factor that’s intentionally varied by the experimenter.

Dependent Variable o the factor that is measured. may change as a result of the independent variable. is the same for every group in the experiment

Scientists create and conduct experiments to test their hypothesis.

Experimental Design To get conclusive test results, experimenters rely on certain practices.

Control Group  the group that serves as the standard of comparison.  may be a “no treatment" or an “experimenter selected” group.  is exposed to the same conditions as the experimental group, except for the IV.

The Control in an Experiment What is a control? The part of the experiment that serves as the standard of comparison. Why is a control necessary? It is the unchanged part of the experiment that detects the effects of hidden variables.

Experimental Group Group that receives experimental treatment May be several smaller groups that each receives different amounts of the IV. Measures the same DV as the control group.

Constants in an Experiment What are constants in an experiment? Factors that are kept the same and not allowed to change

Gather and analyze data O Data-Results of the experiment O May be quantitative (numbers) or qualitative. O Data must be organized in order to be useful. O Can be organized into charts, tables, or graphs

Which Graph Should I Use? USE A BAR GRAPH To compare data on similar things USE A LINE GRAPH To show changes and trends over time. USE A CIRCLE GRAPH To show parts of a whole.

Graph set up Title Title for the Independent Variable – include units and an appropriate scale Title for the DependentVariable – include units and an appropriate scale y x

Constructing a Graph What is the purpose of a graph? Graphs communicate in pictorial form the data collected in an experiment

Scientific Measurement

In science, measurement is the process of obtaining the size or amount of an object relative to a unit of measurement. The term can also be used to refer to the result obtained after performing the process.

Can you name some units that we use? Liquid ______________________ Mass ______________________ Length ______________________ Temperature __________________ Time ________________________

In the metric system, we will be using the following terms: Grams (Mass) Liters (Volume) Meters (Length) Seconds (Time) Degrees Celsius (Temperature).

Metric System

Official Name: International System of Units (SI) Official Name: International System of Units (SI) was devised by French scientists in the late 18 th century. was devised by French scientists in the late 18 th century. goal -to produce a single unified system that could be used throughout the entire world. goal -to produce a single unified system that could be used throughout the entire world.

Metric System is based on a base unit that corresponds to a certain kind of measurement is based on a base unit that corresponds to a certain kind of measurement  Length = meter  Volume = liter  Weight (Mass) = gram Prefixes plus base units make up the metric system Prefixes plus base units make up the metric system Example: Example:  Centi + meter = Centimeter  Kilo + liter = Kiloliter

Metric Prefixes Kilo (k)meaning 10 3 hecto(h)meaning 10 2 deka(da)meaning 10 1 BASE UNIT---meters, Liters, grams deci(d)meaning deci(d)meaning centi(c)meaning centi(c)meaning milli(m)meaning milli(m)meaning micro(u)meaning micro(u)meaning “King Henry died by drinking chocolate milk!’ Move decimal RIGHT Move decimal Left

Draw Conclusions O What did you find the answer to the question was? O Accept or Reject your hypothesis. O It is OK if it turns out that your hypothesis was not correct.

Possible Experimental Errors What factors in your materials or procedure might have had an impact on your results?

Once a scientist completes an experiment, they often repeat it to see if they get the same findings and results. O This is really what we call verification, or checking things out to make sure everything was valid and will happen again and again.

Errors mistakes made during the experiment

Types of errors Sampling – when there are not enough members of a population studied. The larger the population studied, the less likely for a mistake to have been made. Human – any mistake the researcher makes during the experiment. This can include wrong measurements, not following directions, etc…

Retest In order to verify the results, experiments must be retested.

Scientists share their experiments and findings with others. O Because they share their experiments and findings, scientists can learn from each other and often use someone else’s experiences to help them with what they are studying or doing.