Scientific Method Section 1.1

A. Scientific Methodology One Goal of Science provide natural explanations for events in natural world Use those explanations understand patterns in nature and to make useful predictions about natural events

B. Steps of Scientific Method Observations: act of noticing and describing events in a careful, orderly way these observations lead to Questions or problems which need to be solved 2. Hypothesis: possible explanation for problems or questions that can be tested

3. Controlled Experiment (test) - only one variable is changed a) control group: exposed to the same conditions as experimental group except for one Independent Variable (IV)

4. Collect/ Record/ Analyze Data – a) Qualitative Data: Words b) Quantitative Data (numbers; measurements)

5. Conclusions – experimental data is used as evidence to support, refute, revise your hypothesis.

C. Identifying Variables 1. Every experiment involves several variables –factors that can be changed

Independent Variables Also called “manipulated variable” or IV This is the variable you purposely change and test Example: the temperature of the a room

Dependent Variable Also called – “responding variable” or DV The factor that may change as a result of the Independent Variable Example: how fast plants grow in response to the temperature change.

Controlling Variables Keeping all conditions the same except for the Independent Variable (IV) Example: size of the container, type of soil, amount of sun, amount of water, use of fertilizer, same kind of seeds When all variables are controlled, you can then conclude that the differences in your results are due to the changes in the Independent Variable (IV)