The Scientific Method The Scientific Method State Problem

The Scientific Method

The Scientific Method • State Problem / gather information – Why or how questions – Question must be testable – emotion and values not testable • “There are other laws of physics that we can not measure. ” • Form a Hypothesis – Answer your question with and educated guess – In form of if/then statement – “If I increase the temperature, the speed of the reaction will also increase. ” • Test Hypothesis (experiment) • Analyze Data – Tables and Graphs • Draw Conclusion – Does the data support your hypothesis

Flow Chart

Question • SPAM – Simple – Practical – Answerable – Measurable

Hypothesis • If…then…will….

Experiments • Changed Variable • Measured Variable • Controlled Variables – Things you keep the same. • Bias – Eliminated by running several repeatable trials

Experiment #1 • Ten seeds were planted in each of five pots found around the house that contained 500 g of “Pete’s Potting Soil. ” The pots were given the following amounts of distilled water each day for 40 days: Pot 1, 50 m. L; Pot 2, 100 m. L; Pot 3, 150 m. L; Pot 4, 200 m. L; Pot 5, 250 m. L. Pot 3 received the recommended amount of water. The height of each plant was measured at the end of the experiment.

Answers: Pete’s Potting Soil • Independent Variable: – Amount of distilled water • Dependent Variable: – Height of the plants • Constants: – Type of soil, amount of sunlight, type of plant, type of pot, anything else? • Control(s): – Pot 3 received the recommended amount of water.

Experiment #2 • Gloria wanted to find out if the color of food would affect whether kindergarten children would select it for lunch. She put food coloring into 4 identical bowls of mashed potatoes. The colors were red, green, yellow and blue. Each child chose a scoop of potatoes of the color of their choice. Gloria did this experiment using 100 students. She recorded the number of students that chose each color.

Answers: Colored Potatoes • Independent Variable: – mashed potato color • Dependent Variable: – students choosing to take them • Constants: – mashed potato ingredients, bowls served in, spoons served with, server, student age • Control(s): – How many students normally take potatoes? – A bowl of regular potatoes would need to be set out also.

Law and Theory • Do laws become theories or other way around? • Law: observable facts of nature – rules of the game. – No explanation – this will happen. – Law of Gravity • Theory: An explanation for a set of observations. – Answers why. – Many theories of gravity out there • To become a theory takes many supporting observations.
- Slides: 11