THE SCIENTIFIC METHOD Mrs DAnton TODAYS OBJECTIVES Describe
THE SCIENTIFIC METHOD Mrs. D’Anton
TODAY’S OBJECTIVES -Describe how the scientific method is used. -Explain the purpose of controlling conditions in an experiment. -Differentiate between observations and conclusions -Differentiate between quantitative and qualitative observations
CANDLE ACTIVITY Let’s make as many observations about the unlit candle we can in 2 minutes!
CANDLE ACTIVITY Watch the burning candle for 5 minutes. On a blank sheet of paper, write down 10 observations. - Describe the candle - Describe what is happening - Color and shape of flame - What is burning?
SCIENTIFIC METHOD - The scientific method is a logical method of problem solving. It involves observing and collecting data, formulating hypotheses, testing hypotheses, and formulating theories that are supported by data.
STEPS OF THE SCIENTIFIC METHOD - Making observations that lead to a question - Forming a hypothesis to answer the question - Testing the hypothesis by experiment - Making a conclusion based on the results of the experiment
OBSERVATION. Observation is the use of the senses and devices in the lab to obtain information. • Data ( a collection of facts) may be: qualitative (descriptive) quantitative (numerical). Let’s practice. Write down whether the observations in Part 2 on your lab are quantitative or qualitative. Take a minute & next to your observations, write down whether it is a quantitative (N) or qualitative (L) observation.
CONCLUSION. A conclusion is a statement based on observations & prior knowledge (eg. The candle is made of wax) Let’s practice. Write down whether the statements in Part 3 are observations or conclusions. Take a few minutes to cross out any conclusions on your observation list.
CANDLE ACTIVITY In your groups, discuss what questions do you have about the candle based on your observations?
HYPOTHESIS. - A scientist forms a hypothesis to answer the question. A hypothesis is a theory or explanation based on observations that can be tested. - A good hypothesis: 1. explains an observation 2. can be tested 3. will predict the outcome of an experiment
CANDLE ACTIVITY Make a hypothesis for the following: -As the candle burns, it gets shorter. Where does the wax go?
EXPERIMENT. An experiment is designed to test a hypothesis. It involves variables. Variables are factors can be varied, that is, are changed. It is performed under controlled conditions.
VARIABLE REVIEW. Control variable is a variable that is held constant. In a good experiment: -Only two variables are allowed to change. -The independent variable is changed. -The dependent variable changes as a result of the experiment -All other variables are controls because they are held constant
CANDLE ACTIVITY Name one variable you would change and the dependent variable that would be affected. Example: Independent variable: Time for candle to burn Dependent variable: Candle mass Controls: Environment (Temperature/Humidity of Room)
CANDLE ACTIVITY Draw your conclusions. Let’s execute one of the experiments. What happened?
THEORY VS LAW Theory is an explanation for phenomenon that is based on experimentation, observation and reasoning. A hypothesis that withstands repeated testing may become a theory. A Law is a statement or mathematical expression that reliably describes behavior in the natural world. A theory attempts to explain it, a law describes the events. A law tells how things work.
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