Nature of Science Notes
- There is a common belief that a Hypothesisbecomes a Theory which becomes a Law,but this is not true
- Terms
- Belief–Personal viewpoints, opinions, thoughts, and ideas which cannot be supported by scientific evidence.
- personal and give meaning to people’s lives
- put things in perspective and context
- are important, but just not science
- Fact–Statement which can be supported by scientific evidence.
- Must be true under specific conditions.
- Some may be found false when re-tested with better instruments.
- Example: Water boils at 212oF (100oC, 373K), but only at sea level.
- In Denver with an elevation of 1 mile it boils at 203oF (95oC, 368 K)
- Hypothesis–Educated guess about the relationship between 2 variables, based on observations and inferences.
- Hypothesis can be tested, beliefs cannot
- Scientific Law( same as a Natural Law) - Logical or mathematical explanation of the relationship between 2 variables, based on repeated experimentation.
- Examples
Boyles’ Law – In a gas a higher pressure means a smaller volume / Newton’s 2nd Law – Force accelerates an object, mass resists acceleration.
- Theory–Explanation of how and why things happen, based on facts and laws.
- The older the theory the more support it has from experimentation, laws and facts.
- Examples:
- Kinetic Molecular Theory
- Atomic Theory (Standard Model)
- Theory of Evolution
- Big Bang Theory
- Facts, Laws, and Hypothesescombine to make up a theory.
Science is / Science is not
Objective
Repeatable
Changeable
Self-Correcting / Based on opinion
Random
Permanent
Unwilling to change when it is wrong
Practice
One of the most difficult things for students and non-scientists to get ‘straight’ are the terms: Theory, Hypothesis, Law, Fact and Belief. This exercise consists of a seriesof statements, which you will mark as a statement of a Theory (T), Hypothesis (H), Fact (F), Law (L) or Belief (B). To help you out each one is used twice, once in the first 5 and once in the 2nd.
_____ 1.The United States is the greatest country on earth. Belief
_____ 2.There are 50 states in the United States. Fact
_____ 3.For every action, there is an equal and opposite reaction. Law
_____ 4.If Water freezes at 32oF, then ice will melt at 32oF. Hypothesis
_____ 5.Through the process of natural selections humans, bonobos, chimpanzees and gorillas evolved from a common ancestor species. Theory
_____ 6.The Milky Way is a spiral-type galaxy Fact
_____ 7.The positions of the planets can cause humans to act in specific ways Belief
_____ 8.If I jump out a window I will die. Hypothesis
_____ 9.Energy can be converted into matter in the ratio of E=mc2 Law
_____ 10.Illness comes from microscopic germs, some of which, bacteria, can be seen under the microscope and cultivated outside a host, and others, viruses, are too small to see under the microscope. Theory