An Introduction to Physics

Biblical Reference

Great are the works of the Lord, studied by all who delight in them.

Psalm 111:2

What Exactly is Physics?• Physics is an inquiry into the world and the

way it works.

• The goal of physics is to use a small number of basic concepts, equations, and assumptions to describe the physical world.

The Founding Fathers of Physics• Archimedes• Kepler• Galileo• Newton• Einstein• Bohr• Heisenberg

17th Century

20th Century

~250 BC

How much math is in Physics?• Physics uses math as a tool to describe

the physical world. Math provides data to support different physical conclusions.

– So the answer is yes, we will use a lot of math, but we will review the math concepts before we use them.

Where can we find Physics?• Sports• Human Body• Game of Pool• Land Vehicles• Air/Space Vehicles• Home• Toys• Amusement Parks• Movie Special Effects

Why learn physics?• Many students ask this question and I can give you

four good reasons to learn physics.

1) Once you learn rules of the game, you can play the game a lot better. Meaning… once you understand the laws of the universe and how those laws apply to your everyday life you will see the world from a different perspective.

2) Problem Solving! You are faced with problems everyday. Physics will make you a better problem solver because it causes you to think and use your brain in different ways.

3) Many of you will be required to take physics in college and I want that experience to be pleasant and not painful.

4) When you tell people you are taking physics, they think you are really smart.

Branches of Physics• Thermodynamics – heat & temperature

• Mechanics – motion

• Optics – light

• Electromagnetism – electricity & magnetism

• Waves and Vibrations – harmonic motions

• Relativity – particle physics

• Quantum mechanics – subatomic particle physics

Where Do Physicists Work?• Engineers (Mechanical,

Electrical, Aeronautical, Civil etc..)

• Astronomers

• Software Developers /Computer Science

• Business and Industry

• Scientist at Universities /Research

Learning Physics• Physics has its own vocabulary and will

require some memorization. However, you will not be successful with memorization alone. You must strive for understanding the concepts. Never forget to ask the question..What does my answer really mean?

• Trial and error will play an important part of your learning. It is okay to make a mistake as long as you learn from it.

• It will take practice.

Scientific Inquiry

Ask Questions• Asking a question is often the first step in

using scientific methods.

• Asking a question usually results from making many observations, using one of more of the five senses.

Form a Hypothesis• After scientists ask a question, their next

step is usually to form a hypothesis.

• A hypothesis is a possible explanation or answer to a question.

• A good hypothesis is a testable idea that leads to scientific investigation.

• A prediction is a statement of what will happen next in a sequence of events

Test the Hypothesis• After scientists form a hypothesis, they

usually test the hypothesis to find out if it is a reasonable answer to their question.

• If the prediction is not confirmed, the hypothesis might need revision

Organize and Analyze Data• Analyzing results by using

tables and graphs helps scientists understand relationships between the data.

Organize and Analyze Data• Scientists must determine whether inferences or

conclusions can be made from the data.– An inference is a logical explanation of an observation

that is drawn from prior knowledge or experience.

• Analyzing data from repeated tests can help scientists determine if their data are accurate and reproducible.– Data are reproducible when you get similar data from

many tests.

• If the hypothesis is not supported, it may have to be modified.

Draw Conclusions• After scientists analyze the results, they draw

conclusions about whether their hypothesis was supported.

• Valid conclusions can only be obtained with reproducible data.

– Data are considered reproducible when scientists get similar data from many repeated tests.

– Reproducible data helps scientists make sure that the results of their experiment were not an accident

Communicate the Results• After drawing conclusions, scientists often

communicate their results.

• When scientists communicate their results, it allows others to continue the investigation.

• Results can be communicated through scientific papers, presentations, and the Internet.

Scientific Theory and Law• A scientific theory is an explanation

of observations or events based on knowledge gained from many observations and investigations.

• A scientific law describes a pattern or an event in nature that is always true.

Scientific Theory and Law• Critical thinking is comparing what you

already know with the information you are given in order to decide whether you agree with it.

Scientific Theory and Law• To prevent bias in an investigation, sampling,

repetition, and blind studies can be helpful.– Bias: Intentional or unintentional prejudice

towards a certain outcome.

– Sampling: A small, random representation of the whole population

– Repetition: Experiments are conducted multiple times to ensure the results are valid.

– Blind Studies: The investigator, subject or both do not know which sample they are testing.

Scientific Theory and Law• Questions about personal opinions, values,

beliefs, and feelings cannot be answered scientifically.

• Scientists follow safety procedures when they conduct investigations.

• Ethics are especially important when using living things during investigations