Intro to Physics – Matter & Energy

1. Intro to Physics – Matter & Energy http://www.aplusphysics.com/courses/honors/intro/matter_energy.html Unit #2 Kinematics

2. Objectives and Learning Targets • Understand the question, “What is Physics?” • Identify and explain several disciplines within the study of physics • Define mass, matter, work, and energy Unit #2 Kinematics

3. What is Physics? • Book definition has to do with… matter energy interactions But, the real question is “Why?” Examples: Why is the sky blue? Why do objects fall? Unit #2 Kinematics

4. Matter… • Matter – anything that has mass and takes up space • Think of it as the amount of “stuff” in something • Examples of matter: solids (rocks, metals, etc.), liquids (water, vinegar, etc.), gases (helium, nitrogent, oxygen), plasma (sun, stars) Unit #2 Kinematics

5. Sample Problem #1 Unit #2 Kinematics

6. Sample Problem #1 Unit #2 Kinematics

7. Types of Mass • Inertial Mass – an objects resistance to being accelerated by a force • The more inertial mass, the harder it is to accelerate the object of interest • Gravitational Mass – the amount of gravitational force experienced by an object • The more gravitational mass, the more gravitational force • Both types of mass are generally equal for practical purposes Unit #2 Kinematics

8. Energy • Energy – often defined as the ability to do work or make a change in something • What is Work? • Work – the process or capacity to move an object • Both definitions are vague, because energy is often difficult to define Unit #2 Kinematics

9. Mass-Energy Equivalence • Scientists around the turn of the century proposed a strong relationship between matter and energy • 1905 Albert Einstein formulated E=mc2, which show matter and energy are really one in the same • Led the way to nuclear energy, nuclear weapons, particle colliders, etc. Unit #2 Kinematics

10. Galileo - 1609 • developed a systematic method of observing, experimenting, and analyzing…the scientific method • B. no set method – but scientists started to systematically analyze problems, along with keeping detailed records Unit #2 Kinematics