Curiosity inquiry and are the starting points for learning about the natural world. science However, investigating questions in, finding solutions to, problems and deciding on appropriate courses of action in different situations are not simple one-step tasks. Each of these skills is actually a multi-step process called the. Scientific Method Is there only one scientific method? I m glad you asked that 1
NO versions, there are several. steps Some versions have more while others may have only a few, like the one on the earlier page. However, they all begin with the identification of a question or problem to be answered based on observations of the world around us and provide an organized system for conducting and an experiment. analyzing Example: Falling Objects Aristotle vs. Galileo Brainiac Video Feather & Hammer Drop on the Moon 2
Observe Ask a Question Redo! Hypothesize Experiment/Research Redo! Analyze Results Hypothesis support Conclude Report/Share Hypothesis NOT supported Doing Science vs. Thinking Science The Scientific Inquiry Model that we just looked at is a great example of how to DO science. But science isn t always about doing. Don t get me wrong doing has a very important place in science but isn t the entire picture. 3
Doing Science vs. Thinking Science THINK There is also a way to scientifically or to put it another way to THINK like a. scientist doing thinking While and about science are closely related and in many ways, connected they have a slightly different approach and can be used at different times. observations For instance, when you make in everyday life, and generate a, question you may want to do an experiment or use the Scientific Method. But at other times, you may not be able to do an experiment, so doing the scientific method may not always be appropriate or applicable. 4
Does this mean that science is no longer useful?? If we only see science as the Scientific Method we may fall into this trap. But fear not! Science is not just limited to this narrow definition. There is more to science than just doing the Scientific Method. There is a way to THINK scientifically. 5
While there are many ways to think scientifically we are going to focus on 3 questions that will lead out discussion. In order to think scientifically about something, or be scientifically, literate we are going to consider the following questions:? Is it scientific? Can it be trusted? Can I explain it Each of these questions comes with important criteria: Is it Scientific? (Does it play by the rules of Science?) Focuses on and aims to describe the natural world Created from testable ideas (falsifiable) Produces, objective measureable evidence Leads to ongoing research Involves the scientific (peer reviewed) community 6
Can it be trusted? Information comes from and sources reliable credible community Accurately describes the views of the scientific Issue is not sensationalized or made purposefully controversial Includes supporting or evidence to available research and more information Includes links or references to available research and more information Can I explain it? Identify the points Use concrete words and examples FROM THE TEXT! Written in simple sentences without unnecessary words or adjectives Written for the intended audience - Proof important read 7
As you can see, these criteria turn almost into a type of checklist in order to consider things scientifically. If one criterion isn t met it may still be considered scientifically sound but if several criteria are missing the issue or topic becomes highly suspicious from a scientific view or way of thinking. Here s the thing this sounds kinda mean and maybe a little bit harsh but science doesn t care what you think or how you. feel facts Science is concerned with. What we can prove and what we know for sure. It is a way of understanding the world and navigating through the minefield of information that exists all around us. Science seeks to discover the regardless of what you personally. believe truth 8
Units, Units, Units! Scientific Skills Are Units Important in Science? YES Describe the size of something!!! Units of measurement are the terms that we use to. You probably know that units include things like seconds, kilograms, meters, and so forth. Without standard units of measurement, scientists would have a huge problem understanding what other scientists were saying. After all, if I were to refer to a meter as "the length of my leg" and another scientists were to refer to it as "the length of a Saint Bernard dog", we'd have a lot of trouble when it came to do actual science. To avoid this problem, the SI system of units gives us a that we can agree on. Standard set of units 9
Although there are other systems of measurement, the two most common are the Système International (SI) and the system. Imperial In Canada, the official system of measurement is the. SI Because of Canada s close proximity to the United States, you should be familiar with both systems. Both are used in certain contexts. : Système International the modern version of the metric system; uses the metre as the basic unit of length : Imperial system the system most commonly used in the United States; the standard unit of measurement for length is the foot If you look at a ruler marked in imperial units, you will notice that it is usually divided into halves, quarters, eighths, and sixteenths, whereas the SI system uses tenths. 10
Below are listed some common imperial units of length and their relationships. 12 inches (in or ) = 1 foot (ft or ) 36 inches = 1 yard (yd) 3 feet = 1 yard 5280 feet = 1 mile (mi) 1760 yards = 1 mile Importance of Significant Figures, Scientific Notation, Decimals & Rounding 1. SIGNIFICANT FIGURES (SIG FIGS) necessary Significant figures are those digits to express the results of a measurement to the precision with which it was made. No measurement is ever absolutely correct since every measurement is by limited the accuracy or of the instrument used. reliability 11
Ex: if a thermometer is graduated in one degree intervals and the temperature indicated by the mercury column is between 55 C and 56 C, then the temperature can be read precisely only to the nearest degree (55 C or 56 C, whichever is closer). If the graduations are sufficiently spaced, the fractional degrees between 55 C and 56 C can be estimated to the nearest tenth of a degree. If a more precise measurement is required, then a more precise measuring instrument (e.g., a thermometer graduated in one-tenth degree intervals) can be used. This will increase the number of significant figures in the reported measurement. In dealing with measurements and significant figures the following terms must be understood: Precision tells the reproducibility of a particular measurement or how often a particular measurement will repeat itself in a series of measurements. Accuracy tells how close the measured value is to a known or standard accepted value of the same measurement. 12
Measurements showing a high degree of precision DO NOT always reflect a high degree of accuracy nor does a high degree of accuracy mean that a high degree of precision has been obtained. It is quite possible for a single, random measurement to be very accurate as well as to have a series of highly precise measurements be inaccurate. Ideally, high degrees of accuracy and precision are desirable, and they usually occur together, but they are not always obtainable in scientific measurements. Every measuring device has a series of or markings graduations on it that are used in making a measurement. The precision of any measurement depends on the of the markings. size smaller more The the interval represented by the marking, the precise the possible measurement. 13
accuracy The of a measuring device depends on how exact the graduations are marked or engraved on the device in reference to some measurements. standard For most measuring devices used in everyday work, the graduations on them are usually sufficiently for general use. accurate In the laboratory, it is not always advisable to accept a measuring device as accurate unless the instrument has been calibrated. Calibration is the process of checking the graduations on a measuring device for. accuracy 14
Whether the information from a series of measurements is obtained first-hand or second hand through another source, the number of significant figures must be determined in order to keep all the results meaningful. The rules for writing and identifying significant figures are: 15
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two three three six three four three one 2. ROUNDING-OFF SIG FIGS NUMBERS When dealing with significant figures, it is often necessary to Round-off numbers in order to keep the results of calculations. significant three To round-off a number such as 64.82 to significant figures means to express it as the nearest three digit number. Since 64.82 is between 64.8 and 64.9, but closer to 64.8, then the result of the round-off is 64.8. 18
A number such as 64.85 is equally close to 64.8 and 64.9. In this case and in similar cases, the rule to observe is to Round-off to the nearest number which is 64.8. even This rule assumes that in a series of numbers which are to be rounded off, there will be approximately the same number of times that you would have to round-off upward to the nearest even number as you would have to round-off. downward 19
63.4 0.000000440 10200000 556 0.00203 9.10 x 10 4 3.80 7.30 x 10 3 20