intro to physics – matter & energy unit #2 kinematics
TRANSCRIPT
Intro to Physics – Matter & Energy
http://www.aplusphysics.com/courses/honors/intro/matter_energy.html
Unit #2 Kinematics
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
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
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
Sample Problem #1
Unit #2 Kinematics
Sample Problem #1
Unit #2 Kinematics
Types of Mass
Unit #2 Kinematics
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
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
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
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