Class Summary

Introduction Section 0 Lecture 1 Slide 1

Lecture 38 Slide 1

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Physics of Technology

PHYS 1800

Lecture 38

Class Summary

Class Summary

Introduction Section 0 Lecture 1 Slide 2

Lecture 38 Slide 2

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

PHYSICS OF TECHNOLOGY Spring 2009 Assignment Sheet

*Homework Handout

PHYSICS OF TECHNOLOGY - PHYS 1800 ASSIGNMENT SHEET

Spring 2009 Date Day Lecture Chapter Homework Due Feb 16 17 18 19 20

M Tu W H F*

Presidents Day Angular Momentum (Virtual Monday) Review Test 2 Static Fluids, Pressure

No Class 8 5-8 5-8 9

-

Feb 23 25 27

M W F*

Flotation Fluids in Motion Temperature and Heat

9 9 10

6

Mar 2 4 6

M W F*

First Law of Thermodynamics Heat flow and Greenhouse Effect Climate Change

10 10 -

7

Mar 9-13 M-F Spring Break No Classes Mar 16 18 20

M W F*

Heat Engines Power and Refrigeration Electric Charge

11 11 12

8

Mar 23 25 26 27

M W H F*

Electric Fields and Electric Potential Review Test 3 Electric Circuits

12 13 9-12 13

-

Mar 30 Apr 1 3

M W F

Magnetic Force Review Electromagnets Motors and Generators

14 9-12 14

9

Apr 6 8 10

M W F*

Making Waves Sound Waves E-M Waves, Light and Color

15 15 16

10

Apr 13 15 17

M W F*

Mirrors and Reflections Refraction and Lenses Telescopes and Microscopes

17 17 17

11

Apr 20 22 24

M W F

Review Seeing Atoms The really BIG & the really small

1-17 18 (not on test) 21 (not on test)

No test week 12

May 1 F Final Exam: 09:30-11:20am * = Homework Handout

Class Summary

Introduction Section 0 Lecture 1 Slide 3

Lecture 38 Slide 3

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Physics of Technology

PHYS 1800

Lecture 39

So What Does It All Mean?

Class Summary

Introduction Section 0 Lecture 1 Slide 4

Lecture 38 Slide 4

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

What is Physics?

“Study of the basic nature of matter and the interactions that govern its behavior.”

BORING!!!

“How Stuff Works.”

True, but vague.

“Common Sense Approach to How Things Work”(with units!)

Common Sense—A minimal set of simple, straightforward guides.

Units—Predictions on a quantitative level

Class Summary

Introduction Section 0 Lecture 1 Slide 5

Lecture 38 Slide 5

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Scientific Method:

Leads to new discoveries → how scientific progress is made!

Careful measurements,

Experiments

Empirical laws,

Generalization

Hypothesis,

Theory

Class Summary

Introduction Section 0 Lecture 1 Slide 6

Lecture 38 Slide 6

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

How are scientific explanations/laws developed?

1. Careful observations reveal an unknown natural phenomena…(try to find answers - read books, search web…)

2. Gather facts and measurements about phenomena, study other people’s ideas and try to develop an “empirical law” based on your results.

3. Invent a “hypothesis” to explain your observations and empirical laws.

4. Develop experiments to test your hypothesis. (Controlled experiments in laboratory preferably.)

5. Publish your results in scientific literature. (critical review…)

Class Summary

Introduction Section 0 Lecture 1 Slide 7

Lecture 38 Slide 7

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Why study everyday phenomena?

The same physical principles that govern our everyday experiences also govern the entire universe

– A bicycle wheel, an atom, and a galaxy all operate according to laws for angular momentum.

Class Summary

Introduction Section 0 Lecture 1 Slide 8

Lecture 38 Slide 8

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

What Do We Need To Measure?

What is the minimum about things we need to know?

Where things are—a length, LWhen things are there—a time, t

How thing interact with gravity—a mass, MHow things interact with E&M—a charge, Q

How thing interact with weak nuclear forceHow things interact with strong nuclear force

Random collections of objects—a temperature, T

Class Summary

Introduction Section 0 Lecture 1 Slide 9

Lecture 38 Slide 9

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Describing Motion

Position—where you are in space (L-meter)

Speed—how fast position is changing with time (LT-1 or m/s)

Acceleration—how fast speed is changing with time (LT-2 or m/s2)

Class Summary

Introduction Section 0 Lecture 1 Slide 10

Lecture 38 Slide 10

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Dennison’s Laws of Motion

1. Stuff happens (or not).

2. The bigger they are the harder they fall.

3. You get what you give.

Class Summary

Introduction Section 0 Lecture 1 Slide 11

Lecture 38 Slide 11

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Newton’s Laws in Review

1st Law —a special case of the 2nd Law for statics, with a=0 or Fnet=0

• An objects velocity remains unchanged, unless a force acts on the object.

2nd Law (and 1st Law)—How motion of a object is effected by a force.

– The acceleration of an object is directly proportional to the magnitude of the imposed force and inversely proportional to the mass of the object. The acceleration is the same direction as that of the imposed force.

3rd Law —Forces come from interactions with other objects.

• For every action (force), there is an equal but opposite reaction (force).

F ma

units : 1 newton = 1 N = 1 kgm s2

Class Summary

Introduction Section 0 Lecture 1 Slide 12

Lecture 38 Slide 12

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Describing Motion and InteractionsPosition—where you are in space (L or meter)

Velocity—how fast position is changing with time (LT-1 or m/s)

Acceleration—how fast velocity is changing with time (LT-2 or m/s2)

Force— what is required to change to motion of a body (MLT-2 or kg-m/s2 or N)

Inertia (mass)— a measure of the force needed to change the motion of a body (M)

Energy—the potential for an object to do work. (ML2T-2 or kg m2/s2 or N-m or J)

Work is equal to the force applied times the distance moved. W = F dKinetic Energy is the energy associated with an object’s motion. KE=½ mv2

Potential Energy is the energy associated with an objects position.Gravitational potential energy PEgravity=mghSpring potential energy PEapring= -kx

Momentum— the potential of an object to induce motion in another object (MLT-1 or kg-m/s)

Angular Momentum and Rotational Energy— the equivalent constants of motion for rotation (MT-1 or kg/s) and (MLT-2 or kg m/s2 or N)

Class Summary

Introduction Section 0 Lecture 1 Slide 13

Lecture 38 Slide 13

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Dennison’s Laws Thermal Poker(or How to Get a Hot Hand in Physics)

0th Law: Full House beats Two Pairs

1st Law: We’re playing the same game (but with a wild card)

2nd Law: You can’t win in Vegas.

3rd Law: In fact, you always loose.

0th Law: Defines Temperature

1st Law: Conservation of Energy (with heat)

2nd Law: You can’t recover all heat losses (or defining entropy)

3rd Law: You can never get to absolute 0.

Class Summary

Introduction Section 0 Lecture 1 Slide 14

Lecture 38 Slide 14

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

The Newton’s Law of gravitation and Coulomb’s Law of electrostatic force has the same inverse-square dependence on distance as.

– If we double the distance between the charges, the force falls to one-fourth of the original.

– The gravitational force depends on the masses, and the electrostatic force depends on the charges.

– Gravity is always attractive; there is no such thing as negative mass.– Gravity is much weaker than the electrostatic force.– Physicists are still trying to understand the reasons for the relative

strengths of the fundamental forces.– The search for a unified field theory that would explain the

relationships between all of the fundamental forces is a major area of research in modern theoretical physics.

Fg Gm1m2

r2 and Fe kq1q2

r2

The Electrostatic and Gravitational Forces

Class Summary

Introduction Section 0 Lecture 1 Slide 15

Lecture 38 Slide 15

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Dennison’s Laws of Fluids

When push comes to shove, fluids are just like other stuff.

• Pascal’s Principle: Pressure extends uniformly in all directions in a fluid.

• Boyle’s Law: Work on a fluid equals PΔV

• Bernoulli’s Principle: Conservation of energy for fluids

Class Summary

Introduction Section 0 Lecture 1 Slide 16

Lecture 38 Slide 16

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Electric Circuits

Dennison’s Law of Circuit Analysis—Follow the electrons with your finger Dummy!

(Conservation of charge and energy)

Class Summary

Introduction Section 0 Lecture 1 Slide 17

Lecture 38 Slide 17

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Waves is waves…they all

– Transport energy

– Interfere

– Reflect

– Refract

– Diffract

– Polarize

Principle of Superposition:When two or more waves combine, the resulting

disturbance or displacement is equal to the sum of the individual disturbances.

Waves

Class Summary

Introduction Section 0 Lecture 1 Slide 18

Lecture 38 Slide 18

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

What are the major subfields in Physics?

Classical Physics (pre 20th century)– Mechanics → forces, motion– Thermodynamics → heat, temperature– Electricity and magnetism → charge, currents – Optics → light, lenses, telescopes

Modern Physics (20th century)– Atomic and nuclear → radioactivity, atomic power

– Quantum mechanics } → basic structure matter– Particle physics– Condensed matter → solids and liquids, computers,

lasers– Relativity, Cosmology → universe, life!

Class Summary

Introduction Section 0 Lecture 1 Slide 19

Lecture 38 Slide 19

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Current State of Physics cira 2009

Electricity & MagnetismMaxwell Equations (c 1880)

Weak Nuclear Force Radioactivity

Strong Nuclear ForceComposition of subatomic particles

Mechanics (Gravity)…… General RelativitySpace and time

Standard Model • QCD• Unites E&M, Strong NF, Weak NF

Conservation Laws• Energy• Linear & Angular Momentum• Charge, Spin• Lepton and Baryon Number

Quantum Mechanics•Schrodinger/Dirac Equation•Probabilistic approach

Statistical Mechanics• Physics of many particles• Fermions and Bosons• Partitioning of Energy• Thermodynamics• Time and Entropy

Weinburg-Salom Model• QED• Unites E&M, Weak NF

Class Summary

Introduction Section 0 Lecture 1 Slide 20

Lecture 38 Slide 20

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Limits of Current Modern Physics

Dimension Range of Applicability

Range of Application

Length 10-18 to 10+26 m Quark size to the universe size

Mass 10-31 to 10+40 kg Electrons to galactic clusters

Time 10+3 to 10+22 sec-1

10-16 to 10+17 sec

Radio to Gamma rays

Sub-femtosecond spectroscopy to age of universe

Velocity 10-8 to 10+8 m/s Sub-atomic particles to speed of light

Class Summary

Introduction Section 0 Lecture 1 Slide 21

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INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Objectives: This course provides a conceptual introduction to physics with three primary goals:

(1) to gain physical intuition (2) to develop problem solving skills (3) to learn to apply some basic physics principles to everyday phenomena.

PHYSICS OF TECHNOLOGY

Class Summary

Introduction Section 0 Lecture 1 Slide 22

Lecture 38 Slide 22

INTRODUCTION TO Modern Physics PHYX 2710

Fall 2004

Physics of Technology—PHYS 1800

Spring 2009

Top Ten List of Things I Hope You Learned1. Don’t waste your time remembering lots of equations or vocabulary

(that’s what your book is for); go for the concepts!2. There is not that much that we kneed to know (where stuff is and how

stuff interacts)…3. But the range of applications is enormous.4. There are just four fundamental forces in nature. Newton’s Laws turn

these into motion.5. Stuff (mass, charge, energy, momentum, angular momentum) is

conserved.6. Your every day intuition is not always reliable (e.g., E&M, QM,

relativity); you must rely on the careful, logical organization of observations to make valid predictions.

7. Our models reflect the patterns in nature (e.g., waves, oscillations and rotation are described by very similar math).

8. We know a lot of things about nature, but not everything (ask your grandkids to explain the TOE to you.).

9. Physics provides a (often useful) framework and methods to solve a wide variety of problems based on simple rules.

10.“With great power come awesome responsibility…”