Welcome

Physics 102Professor Lee

CarknerLecture 1

Questions to Consider

Am I in the right place? Physics 102: Principles of Physics

Do I have the right stuff? James Walker, “Physics” Lab manual Calculator WebAssign card

available at register at Runestone Bookstore

Things to Know Professor

Dr. Lee Carkner

Office Hours MWF 10-11am Science 208

Help session: TBA

Lab section See me after class to change

How Does the Class Work?

Read the book material before class Do the WebAssign homework

Come to class Do the PAL discussion questions

Lab once a week Two tests and final

Web Page

http://helios.augustana.edu/~lc/ph102

Outline gives homework and readings

Lectures posted online before class Syllabus and WebAssign guide also

posted

Grading

Two tests -- 30% Final -- 25% Homework -- 15% PAL -- 10% Lab -- 20%

WebAssign Homework will be entered and graded online

At webassign.com Click on student login Username is your first and last name together (e.g.

“johnsmith”) Institution is “augustana” Password is same as last semester

Augustana ID number if new to class After login, click on the current assignment and complete

it WARNING: Can only submit it twice

If you are new to Webassign read tutorial on class web page

Homework

Homework will generally be from book Will be posted on webpage WebAssign will randomize numbers

Available at noon M,W,F Due at midnight M,W,F

Cannot turn homework in late or make up Can drop lowest three

Each homework worth same amount (100 points) 15% of grade

PAL

What is PAL? Physics Active Learning

Each class you will get a PAL worksheet Contains questions about the material

and feedback opportunities Worth 10% of your grade

Need to come to class Can drop (or skip) three PAL’s

“Physics is your PAL!”

Guidelines for Work Handed In

Written answers must be in complete sentences

Numbers must have units Answers must reasonable

If not reasonable, explain why All work must be neat and easily

readable

Today’s PAL Please answer the first questions:

What is Physics? What are my goals in taking Physics?

Feedback: Please list:

Your major The highest level of math you have taken

(Algebra, geometry, trig, pre-calc, calc) Comments

Answers What is Physics?

Phys"ics (?), n. The science of nature, or of natural objects; that branch of science which treats of the laws and properties of matter, and the forces acting upon it; especially, that department of natural science which treats of the causes (as gravitation, heat, light, magnetism, electricity, etc.) that modify the general properties of bodies; natural philosophy.

--Webster’s Dictionary 1913

What is Physics?

Physics is a way of figuring out how things work

More specifically: what are the underlying rules that govern how things work?

We will deal mostly with classical physics: i.e. How did things work before 1900?

Why Take Physics?

You may need to know how things work

You can learn how to: Use reason and logic Solve problems Use mathematics

It is useful to understand how we know how things work

Thermodynamics

What is thermodynamics? Thermo

Involves temperature

Dynamics Involves mechanics

Thermodynamics is the study of thermal and mechanical energy How do you transform one into the

other?

Where Does Thermodynamics Come

From? Back in the early 1800’s people figured out that you can transform thermal into mechanical energy

Can make a device that turns heat into work A heat engine

Problem: sometimes the engine would turn heat into horrible bodily injury Need to understand what is going on in the

engine

What is this Stuff?

Liquid Nitrogen The liquid form of the nitrogen gas

that makes up air Temperature = 77 Kelvin = -320 F LN will cause frostburn on contact What is it doing?

Boiling Changing phase from liquid to gas

Principles of Thermal Physics

Lets think about the first five key variables in thermodynamics: Heat Work Temperature Pressure Volume

The Pringles Launcher: A Simple Heat Engine

For the Pringle’s launcher: How does the P,V and T of the

material inside the can change? Describe the heat flow How could you measure the work?

LN and Thermodynamics Using LN demonstrates how things are

affected by temperature changes The properties of common objects depend

on temperature The surface of the Earth is at a very

special temperature (~0 Celsius) Most of the universe is not Our common sense about how things works

only applies to a little corner of the universe

Low Temperature Physics

How is heat transformed into energy? Heat will expand a gas which in turn

can do work How does temperature effect

molecular bonds Low T causes bonds to become less

flexible