History of Science Unit 1 - Science

What is physics? https://www.youtube.com/watch?v=AEIn3T6nDAo Ask if there were any questions on the reading. Review what physics is and show the video. In order to give us a good foundation into physics we are going to look into the history of science just like Sheldon did.

History of Science: Over the centuries, mankind has used a variety of methods to try and explain the world around him. Let’s examine one specific question and how the answers have changed over time. This will demonstrate the gradual development of our current scientific process.

The Various ANSWERS over time: QUESTION: Why does the sun rise and set each day? The Various ANSWERS over time:

Answer: Apollo drives his golden chariot across the sky each day. Superstition: Ancient Man didn’t understand why things happened the way they did, but they still made many important observations about the world around them. They decided to blame everything on supernatural beings. Their explanation for everything was simple: the gods did it. Therefore they used magic and religion to explain everything. Strength: At least they came up with a reason. And you must admit, it works for absolutely everything! Weakness: Very passive explanation. It did not empower mankind with the ability to control the world around them.

Answer: The sun dwells in the heavens. The heavens are perfect. The only perfect shape is a circle. Therefore the sun travels in a circle each day as it goes around the earth and returns to us. 2. Philosophy: Aristotle was one of many ancient philosophers that tried to explain the world through abstract logic. (Which means you can’t really touch it or test it. It exists only in your mind.) Instead of blaming the gods, he tried to think of possible explanations for natural phenomena. Therefore philosophy is based on logic and ideas, not experimentation. Strength: Believed that nothing happens without a cause. There must be a logical reason for everything. Weakness: Focused too much inside his own head (logic) instead of carefully watching what was outside his head (observations).

Awareness test https://www.youtube.com/watch?v=Ahg6qcgoay4 After talking about the Talk about the importance of being aware and making observations because that is where the scientific method starts.

Answer: The sun does NOT go around the Earth. Instead, the Earth goes around the sun. 3. Scientific Revolution: Galileo is often referred to as the “Father of Modern Science”. This is because he was one of the first to actually design experiments and test his ideas. For example: He built his own telescope so that he could study the sun himself. His research led him to believe the above answer. Therefore he used experiments and observations to generate theories. Strength: Based his theories on actual observations and experiments, NOT on guesses. Instead of telling the world how it should work, Galileo was willing to watch the world and accept how it did work. Weakness: Made the Catholic Church very, very angry because no one likes being told that they are wrong. Galileo had no idea why things did what they did he just described how they fell.

Answer: All objects in the universe pull on each other (Law of Universal Gravitation). This is what keeps the Earth in orbit around the sun. The strength of that pull can be modeled very precisely with the following equation: F = Gm1m2/r2 4. Mathematics: Sir Isaac Newton revolutionized Physics by using advanced math to accurately describe and predict the behavior of objects. He did this by collecting observations from many different areas and developing mathematical laws (equations) to match them all. Therefore he used math formulas to describe natural patterns. Strength: The use of math allowed mankind to predict the motion of objects with great accuracy. This allowed us to control the world around us in many ways. Combines both how things work (math formulas predict it very precisely) and why things happen (law of universal gravitation says that all objects with mass pull on each other) Weakness: A lot of people hate math. Still leaves some questions unanswered. Why do all objects with mass pull on each other?

Answer: Objects with mass actually bend the space around them. This causes objects to “fall” towards them because of the curvature of space itself. The sun bends the solar system into a “cosmic bowl” and the planets roll around it like marbles. 5. Modern: Einstein decided to expand on Newton’s math to include a wider variety of situations. Developed a theory for what gravity is. Therefore this phase tries to explain WHY the universe is the way it is. Strength: Much broader applications. (Einstein’s equations apply to a lot of situations that Newton’s do not.) Finally giving answers to what gravity is instead of just describing its effects. Weakness: Hurts just to think about. Yet again, doesn’t answer all the questions. What causes space to bend?

Political Power and Science are linked. The Trend: Political Power and Science are linked. Whatever country rules science rules the world. Aristotle was Greek. Galileo was Italian. Newton was English. Einstein although German studied in America. Comparing this to history itself: One of the first major civilizations were the Greeks. They were then conquered by the Romans (Rome is in Italy by the way). The Roman Empire fell and was later replaced by the British Empire. The British Empire then fell and has since been replaced by the United States as a major world super power.

So… Political power and science are linked. Aristotle = Greece = Greek Empire Galileo = Italy = Roman Empire Newton = England = British Empire Einstein = America = current superpower Political power and science are linked. Whatever country rules science rules the world.

Scientific Proof Proving something is TRUE is hard! To prove all ducks have feathers you must find EVERY duck in the world! Proving something is FALSE is easy! To prove NOT all ducks have feathers you only need ONE counterexample. Therefore, scientists do NOT try to prove something is true. Rather, they try to prove it is false. If they can’t, then it is accepted as a theory.

Variables Independent variable: Dependent variable: What we Change In a data table it goes on the Left In a graph it goes on the x - axis Dependent variable: What we measure In a data table it goes on the Right In a graph it goes on the y - axis

Data Tables & Graphs Data table columns should ALWAYS include Labels and Units Both graph axes should ALWAYS include Labels and Units Labels and units should be written like this: Label (Units)