SCIENTIFIC EXPERIMENTS Scientific Method scientific method the steps

SCIENTIFIC EXPERIMENTS

Scientific Method • scientific method - the steps a scientist follows to answer a question or solve a problem including… 1. Make Observations & Ask a Question 2. Conduct Research 3. Form a Hypothesis 4. Test a Hypothesis/Conduct an Experiment 5. Analyze Results 6. Draw a Conclusion

Scientific Method 1. Make Observations & Ask a Question • observation – any use of the senses to gather information • inference - conclusions or deductions based on observations and prior knowledge – Process of drawing a conclusion from given evidence

2 Types of Observations Quantitative (quantity) • Deals with numbers • Can be measured – Length, height, area, volume, weight, speed, time, temperature, humidity, sound levels, cost, etc. Qualitative (quality) • Deals with descriptions • Can be observed but not measured – Colors, textures, smells, tastes, appearance, beauty, etc. data - facts, figures, and other evidence gathered though observation

Scientific Method 1. Ask a Question • Questions help you narrow and focus investigation and identify what you are trying to find out. • There are 3 ways to ask a question: – What factors cause… – What is the relationship between… – What is the effect of… 2. Conduct Research • Becoming knowledgeable about the topic and what others have done regarding the question at hand is extremely important.

Scientific Method 3. Form a Hypothesis • hypothesis - possible explanation or answer to a question • If/then statements – The “IF” part is doing what – The “THEN” part is what will happen – Ex: “If I study 10 minutes every night, then I will get an A+ in Science class” • must be testable 4. Test a Hypothesis • To test a hypothesis is to conduct an experiment

Testing a Hypothesis • controlled experiment - experiment where all factors but one are kept constant - only ONE thing tested at a time – factors that are changed in an experiment are variables – those that are not changed are constants/controls

Two Groups in a Controlled Experimental Group Control Group • changed • not changed • used to test something • used for comparison • Ex. Student studying 10 minutes every night • Ex. Student not studying

Two Groups in a Controlled Experiment

Which Group Do You Want to Be In? Control Group Experimental Group

Two Variables in a Controlled Experiment Independent Variable • factor that is changed • the thing being tested • Ex. time spent studying Dependent Variable • factor that changes as a result of the manipulated variable – it DEPENDS of the independent variable • factor that is measured or observed • Ex. grade in Science

Relationship Between the Two Variables v v independent causes dependent if independent … then dependent depends on the independent is caused by the independent

Remembering the Two Variables

Graphing Scientific Variables

Scientific Method 5. Analyze Results 6. Draw a Conclusion • 3 types of conclusions: • In order to understand data collected it must be 1. Supports the hypothesis analyzed to determine if 2. Does not support the hypothesis it supports the hypothesis. 3. Need more information • Regardless of the outcome you must explain