Presentation on theme: "The Scientific Attitude. Accuracy and Precision Accuracy occurs when your experimental data very closely agrees with the known value. If your value is."— Presentation transcript:
Accuracy and Precision Accuracy occurs when your experimental data very closely agrees with the known value. If your value is accurate, that means that it is correct. If your value is not accurate, that means that it is incorrect. ACCURACY: how close a measurement is to the actual (accepted) value Precision refers to how well experimental values agree with each other. If your values are precise, that means that they are very close to each other, whether or not they are correct (accurate). If your values are not precise, that means that they are not very close to each other, whether or not they are correct (accurate). PRECISION: how close measurements are to each other
For each of the following, label the accuracy and precision of the temperature sensor measurements as either high or low. Example 1: Suppose a lab refrigerator holds a constant temperature of 38.0 F. A temperature sensor is tested 5 times in the refrigerator. The temperature from the test are given in the table. Accuracy: Low Precision Low Temperature gained from sensor testing, F 39.4 48.2 28.1 46.3 34.5
Accuracy and Precision A measurement was taken three times. The correct measurement was 68.1 mL. Identify whether the set of measurements is accurate, precise, both, or neither: 68.1 mL, 68.2 mL, 68.0 mL Accurate and precise
Definitions of “Fact” and “Law” Fact: A close agreement by competent observers who make a series of observations of the same phenomenon. A fact is a basic statement established by experiment or observation. All facts are true under specific conditions. Some facts may be false when re-tested with better instruments. Law: A statement that describes a natural phenomena. A law is usually defined by an equation. It is proven true over time. It is a logical relationship between two or more things that is based on a variety of facts and proven hypothesis.
Definitions of “Hypothesis”, “Theory” and “Belief” Hypothesis: An educated guess or a tentative statement such as “if A happens then B must happen” that can be tested by direct experiment or observation. A proven hypothesis can be expressed as a law or a theory. A disproven hypothesis can sometimes be re-tested and found correct as measurements improve. Theory: A reasonable explanation for why certain laws and facts exist that can be tested to determine its accuracy. It is constantly changing. Belief: A statement that is not scientifically provable in the same way as facts, laws, hypotheses or theories. Scientifically disproven believes can still be help to be true.
Identification Identify each statement as a law, fact, hypothesis, theory, or belief: 1. For every action, there is an equal and opposite reaction. Law 2. F=ma Law 3. The Earth is a sphere. Fact 4. Earth’s magnetic field is generated by a conducting fluid in its core. Theory
Identification 5. Water freezes at 32 F. Fact 6. There are such things as ghosts. Belief 7. Some numbers are luckier than others. Belief 8. Primitive human-like creatures existed 2 million years ago. Fact 9. The positions of the planets can cause humans to act in specific ways. Belief
Science, Technology, and Society Science is a method of answering theoretical questions. It discovers facts and relationships between observable phenomena in nature and establishes the theories that organize and make sense of these facts and relationships. Science by itself doesn’t intrude on human life. Technology does. Technology is a method of solving practical problems. It has to do with tools, techniques, and procedures to put the science findings to use. Technologists design, create, or build something for use of humans. However, some technology can have some adverse side effects or create other problems that have to be solved.
Science and Art Science is concerned with discovering and natural phenomena. Science tells us what is possible in nature. The domain of science is natural order. The Art is concerned with the value of human interactions as they are related to the senses. They describe us the human experiences and emotions and suggest us what we should expect from them.