Conceptual Physics

Conceptual Physics 12th grade Christ Chapel Academy

Table of Contents Title Page • Physics • About Science 8 – 13 • Linear Motion 14

Objectives Chapter 1: About Science • Explain why physics is the basic science • Outline scientific method • Distinguish among observations, facts, hypothesis or laws and principles • Distinguish between science and technology • Distinguish among science, art and religion

Common Misconceptions • Physics is the most difficult of the sciences. • Physics is the most basic of the living and nonliving sciences. • Physics has traditionally been more demanding of students than “easier” chemistry and biology courses, because more understanding of the subject is expected in physics.

Common Misconceptions • Physics is applied mathematics • Although mathematics is a language of physics, it is not the only way to study physics.

The Basic Science --- Physics • Science can be placed within two categories: living and nonliving things – the life sciences and the physical sciences. • Life sciences include: biology, zoology, and botany • Physical sciences include: geology, astronomy, chemistry and physics.

The Basic Science --- Physics • Physics is the basics of all the physical sciences! • It’s study includes motion, forces, energy, matter, heat, sound and light. • Biology addresses the WHAT • Chemistry addresses the WHY • Physics address the HOW • Physics Chemistry Biology

Mathematics – The language of Science • Sciences, like physics, that can be expressed in mathematical terms are unambiguous. • When there are findings in nature that can be expressed mathematically. They are easier to verify or disprove by experiment. • Why??????

The Scientific Method • Galileo Galilee and Francis Bacon are credited as the founders of the scientific method.

Con’t The Scientific Method • The Scientific Methodis a logical procedure for choosing an answer to a question. • Why is there a need for the scientific method? • There are no set order activities, individuals will do these following preliminary steps. • 1. Define the problem (narrow) • 2. Research the problem (has anyone else explored this?) • 3. Form the hypothesis (an educated guess) • 4. Perform experiments to test hypothesis • 5. State the outcome (hypothesis was accurate or found to be inaccurate)

The Scientific Attitute • Fact……. An argument made by competent observers who make a series of observations of the same phenomenon. • Is a Hypothesis a FACT????? • When hypothesis are tested over and over and are not found to be contradicted than they become laws or principles!

Continue the Scientific Attitude • Note: a Fact is not immutable and absolute! • Scientists must be prepared to: • Change laws and principles when hypothesis are contracted by other evidences • Change or abandon an idea (something you imagine or picture in your head; Merriam-Webster, 2013) • Accept their findings (even when hypothesis is inaccurate)

Finish Scientific Attitutes • Theory is used differently in science than in normal every day speech…….. • A scientific Theory, is a synthesis of a large body of info that encompasses well- tested and verified hypotheses about certain aspects of the natural world. • Theories can evolve over time…. Making them stronger for the science community. • Scientific attitudes demand order and uniformity.

Scientific Hypotheses (Must be Testable) • Hypothesis are scientific when there is a link to general understanding of nature and follow a cardinal rule. • Cardinal Rule……. IT MUST BE TESTABLE!!!! • Testability is more important than Accuracy of a hypothesis. • Scientific hypothesis test for proving wrongness. • If there is no test for proving it’s wrong then it is not scientific.

Hypotheses that can neither be proven wrong or right are not scientific…. Even if they sound scientific! • Ex. “The alignment of planets in the sky determines the best time for making decisions.” This is speculator…. • Speculation: something that cannot be proven wrong, nor can it be proven accurate. (remember the peanut butter and jelly sandwich)

Bell Work Answer: • (1) Atoms are the smallest particles of matter. • This answer is scientific because there is a test for its wrongness. • The universe is surrounded by a second universe….. Has no test for possible wrongness and is therefore unscientific. • Albert Einstein was the greatest physicists…. Is an assertion (opinion) that has no test for possible wrongness.

Science, Technology and Society • Misconception: science and technology are the same! • Science and technology are not the same! • Science is a “method” of answeringquestions (theoretical) • Technology is the “method” of solvingpractical problems. • Neither are good or bad. What people chose to do with them are good …… or bad!

Review • Read pages: 6 – 7 in your text book • Work on problems 1 – 13 on pg. 8; write the questions and your answers!!!!

Answers to review questions questions(on pg. 8) • The concepts of physics are the foundation of other sciences. • Math is unambiguous; English is more familiar. • It is a method that is effective in gaining, organization, and applying new knowledge. • No scientific facts can change, given compelling evidence • A strength; change can nurture growth.

6. A hypothesis is outside the domain of science if it has no wrongness test. 7. Science answers theoretical questions; technology solves practical problems 8. Both are creative and portray a realm of experience. 9. Science is the study of cosmic order; religion studies cosmic purpose. 10. To give citizens more power over nature and more responsibility.

Chapter 2 Linear Motion • Motion is Relative • Everything moves!!!! • Even when we are at rest, we’re moving….. How? • Your text book may be at rest; however it is moving about 30 kilometers per second (km/s) relative to the sun. • Relative: regarded in relation to something else. • When we discuss the motion of something, we’re really describing its motion relative to something else.

Cheetah’s • When we say that a cheetah is the fasted land animal and can travel 200 meters per (seven) seconds; we’re really saying it’s movement in relation (relative) to the Earth or ground. • When we discuss the speeds of things in our environment we mean speed with respect to the surface of the earth.

Speed • Speed: is a measure of how fast something is moving. • Speed is the rate at which distance is covered • It answers the questions: How long? How Fast? • It’s the rate at which distance is covered • Rate: a quantity that is divided by time

Con’t Speed average speed = total distance covered (km) (m) time interval (s), (min), (h) Instantaneous speed: is speed at any instant Transpose the equations! Distance = speed (x) time Time = distance time

Solving Physics Problems If a cheetah can maintain a constant speed of 25 m/ s, it will cover 25 meters every second. At this rate, how far will it travel in 10 seconds? In 1 minute? What is the question looking for? (clue words) How far (distance) What do I know? Constant speed is 25 m/s What equation(s) will help me solve this problem? Distance = speed (x) time

Average Speed Pyramid d_ v/t Distancespeed/time

Conceptual Physics