Exploring the Scientific Method What does a scientist

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Exploring the Scientific Method

Exploring the Scientific Method

What does a scientist do? Scientists need to Explore Observe Question Classify Make models

What does a scientist do? Scientists need to Explore Observe Question Classify Make models Predicts consequences Make inferences Analyze information

Science ……is to understand the world. A fact is a truth that has been

Science ……is to understand the world. A fact is a truth that has been made from observations or experimentation. No such thing as alternative facts – there is individual perception. Scientists gather evidence and then try to explain using a theory.

Theories in Science A theory is the most logical explanation for events that occur.

Theories in Science A theory is the most logical explanation for events that occur. A scientific theory is a tested concept that makes useful and dependable predictions about the natural world. Theories must be tested many times and are often changed, or added to when more information becomes available.

Laws in Science A law is a scientific theory that has survived many tests

Laws in Science A law is a scientific theory that has survived many tests and never been proven wrong. A law summarizes observed facts.

The Scientific Method The steps of the scientific method (although not always in this

The Scientific Method The steps of the scientific method (although not always in this order): Stating are the Problem Gathering Information on the Problem Forming a Hypothesis Performing Experiments to Test the Hypothesis Recording and Analyzing Data Stating a Conclusion Communicating the results Repeating the Work, if necessary

Stating a Problem You need to have a problem so that you know what

Stating a Problem You need to have a problem so that you know what to study! It is important to make the problem specific. Ex. Do cars with more mass move faster down a hill than cars with less mass?

Gathering Information You must find out everything important that is related to the problem.

Gathering Information You must find out everything important that is related to the problem. Ex. What is mass? Ex. Have any experiments already been done on lighter & heavier cars?

Forming a Hypothesis A suggested solution to the problem is called a hypothesis. A

Forming a Hypothesis A suggested solution to the problem is called a hypothesis. A hypothesis is formed after you have some important information about the problem. Hypotheses can be proven right but not proven wrong – data can SUPPORT (not prove) them. Ex. Cars with different masses should move down a ramp at the same speed.

Performing an Experiment Activities that test the hypothesis are called an experiment. It is

Performing an Experiment Activities that test the hypothesis are called an experiment. It is very important to record the procedures and data, or results, of the experiment. Only one factor or variable can be tested at a time (manipulated or independent variable). We then measure the dependent variable, or what is affected by the change. A control is also used in experiments. This situation is identical to other trials, except the variable is left out so you can compare results.

Repeating the Work Experiments must be repeated several times to make sure the same

Repeating the Work Experiments must be repeated several times to make sure the same conclusion is always reached and to check to see if the results are accurate. Usually 3 -5 repeats are necessary.

Recording and Analyzing Data (dependent variables) During and after an experiment all data is

Recording and Analyzing Data (dependent variables) During and after an experiment all data is recorded and looked at (analyzed). Data includes observations such as measurements (quantitative) or general observations (qualitative). Graphs or charts help us analyze data.

Types of Observations Quantitative Qualitative Mass Color Time Smell Others? Inferences vs Predictions Example:

Types of Observations Quantitative Qualitative Mass Color Time Smell Others? Inferences vs Predictions Example: a broken egg is on the floor by the table. Inference (trying to explain or interpret what you observe based upon what you know) Prediction Has happened Will happen It rolled off the table The mess needs to be cleaned up

Stating a Conclusion After data is analyzed, a scientist states a conclusion. Conclusions either

Stating a Conclusion After data is analyzed, a scientist states a conclusion. Conclusions either find the hypothesis was wrong or the hypothesis was supported. Data from the experiment is used to support the conclusion. Ex. As evidenced by the similar average speeds of each car moving down a ramp, different masses do not make a difference in the car’s speed.