Feedback
Help

Sign In
View Cart

Keyword
Volume/Page
DOI
Advanced

Search Content Type

Volume: Page/Article:

article doi:

Home
Browse
Search
About
Authors
Features
Subscriptions
Advertisers
Scitation
American Journal of Physics

The Physics Teacher»
Browse»

SECTION LISTING

LETTERS TO THE EDITOR
FIGURING PHYSICS
PAPERS
PAPERS
FERMI QUESTIONS
TRICK OF THE TRADE
PHYSICS CHALLENGE FOR TEACHERS AND STUDENTS
YOUTUBE PHYSICS
FOR THE NEW TEACHER
LITTLE GEMS
WEBSIGHTS
BOOK REVIEWS

BROWSE VOLUMES

Year Range:

2012

Volume 50

Issue 5 | May 2012 | pp. 260-318

Issue 4 | Apr 2012 | pp. 198-254

Issue 3 | Mar 2012 | pp. 132-190

Issue 2 | Feb 2012 | pp. 68-126

Issue 1 | Jan 2012 | pp. 6-62

2011

Volume 49

2010

Volume 48

2009

Volume 47

2008

Volume 46

2007

Volume 45

2006

Volume 44

2005

Volume 43

2004

Volume 42

2003

Volume 41

2002

Volume 40

2001

Volume 39

2000

Volume 38

1999

Volume 37

1998

Volume 36

1997

Volume 35

1996

Volume 34

1995

Volume 33

1994

Volume 32

1993

Volume 31

1992

Volume 30

1991

Volume 29

1990

Volume 28

1989

Volume 27

1988

Volume 26

1987

Volume 25

1986

Volume 24

1985

Volume 23

1984

Volume 22

1983

Volume 21

1982

Volume 20

1981

Volume 19

1980

Volume 18

1979

Volume 17

1978

Volume 16

1977

Volume 15

1976

Volume 14

1975

Volume 13

1974

Volume 12

1973

Volume 11

1972

Volume 10

1971

Volume 9

1970

Volume 8

1969

Volume 7

1968

Volume 6

1967

Volume 5

1966

Volume 4

1965

Volume 3

1964

Volume 2

1963

Volume 1

Search Term

Search Issue | RSS Feeds

RSS
Next Issue

Jan 2012

Volume 50, Issue 1, pp. 6-62

Add

View

LETTERS TO THE EDITOR

Select this Article

Units and terms

Carlos H. Wörner

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 6

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable

Show PACS

01.50.-i	Educational aids
32.10.Bi	Atomic masses, mass spectra, abundances, and isotopes

Select this Article

Cartoon by Doug Stith

Doug Stith

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 6

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable

Show PACS

01.50.-i

Educational aids

Select this Article

Female representation among U.S. high school physics students unchanged

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 6

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable

Show PACS

01.50.-i

Educational aids

FIGURING PHYSICS

Select this Article FREE

STEEP WELL

Paul Hewitt

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 8

Full Text: | Download PDF

Abstract Unavailable

Show PACS

01.50.-i	Educational aids
44.25.+f	Natural convection

PAPERS

Select this Article

About the International System of Units (SI) Part III. SI Table

Gordon J. Aubrecht, II, Anthony P. French, and Mario Iona

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 10 | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract

Before discussing more details of SI, we will summarize the essentials in a few tables that can serve as ready references. If a unit isn't listed in Tables I–IV, it is not part of SI or specifically allowed for use with SI. The units and symbols that are sufficient for most everyday applications are given in bold.

Show PACS

01.50.-i	Educational aids
06.20.fa	Units

PAPERS

Select this Article FREE

How Can “Weightless” Astronauts be Weighed?

Jesus Carnicer, Francisco Reyes, and Jenaro Guisasola

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 12

Full Text: Read Online (HTML) | Download PDF

Show Abstract

In introductory physics courses, within the context of studying Newton's laws, it is common to consider the problem of a body's “weight” when it is in free fall. The solution shows that the “weight” is zero¹ and this leads to a discussion of the concept of weight.^2,3 There are permanent free-fall situations such as astronauts in a spacecraft orbiting the Earth, for example, the International Space Station. However, it is important for an astronaut's health to control any variations in his/her body mass while on the orbiting spacecraft. This paper examines the following scenario: How can astronauts be weighed while in free fall?

Show PACS

01.50.Pa

Laboratory experiments and apparatus

Select this Article FREE

The Monty Hall Problem as a Class Activity Using Clickers

Stephen H. Irons

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 14

Full Text: Read Online (HTML) | Download PDF

Show Abstract

Demonstrating probabilistic outcomes using real-time data is especially well-suited to larger lecture classes where one can generate large data sets easily. The difficulty comes in quickly collecting, analyzing, and displaying the information. With the advent of wireless polling technology (clickers), this difficulty is removed. In this paper we describe an activity developed in one of our physics classes to test one of the classic cases of probability in popular culture, The Monty Hall Problem. Using clickers, a paper handout, and stickers, one can easily probe the class opinion on the outcome and then vividly and definitively test it. At the end of the activity, the students have confronted through direct experience the often counterintuitive nature of probability.

Show PACS

01.50.My	Demonstration experiments and apparatus
02.50.Cw	Probability theory

Select this Article

Surface Bubbles in the Bathtub and Reflections on Ripple Tanks

Thomas B. Greenslade, Jr.

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 17

Full Text: Read Online (HTML) | Download PDF

Show Abstract

Bathtubs are splendid places for studying physics! Recently I was happily splashing about and noticed that the light from the lamp above me was being focused as bright spots on the bottom of the tub. Closer inspection showed that the spots were surrounded by dark rings. This pattern turned out to be due to the lensing effect of bubbles floating on the surface of the water.

Show PACS

01.50.My	Demonstration experiments and apparatus
68.03.Cd	Surface tension and related phenomena

Select this Article FREE

Teaching Galileo? Get to Know Riccioli! What a Forgotten Italian Astronomer Can Teach Students About How Science Works

Christopher M. Graney

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 18

Full Text: Read Online (HTML) | Download PDF

Show Abstract

What can physics students learn about science from those scientists who got the answers wrong? Your students probably have encountered little science history. What they have encountered probably has portrayed scientists as “The People with the Right Answers.” But those who got the wrong answers can teach students that in science, answers are often elusive—not found in the back of a book or discovered in a bold stroke of genius.

Show PACS

01.50.-i	Educational aids
01.65.+g	History of science

Select this Article

More on Systematic Error in a Boyle's Law Experiment

Richard P. McCall

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 22

Full Text: Read Online (HTML) | Download PDF

Show Abstract

A recent article¹ in The Physics Teacher describes a method for analyzing a systematic error in a Boyle's law laboratory activity. Systematic errors are important to consider in physics labs because they tend to bias the results of measurements. There are numerous laboratory examples and resources that discuss this common source of error.^2–7

Show PACS

01.50.My	Demonstration experiments and apparatus
01.50.Pa	Laboratory experiments and apparatus
07.07.Df	Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
06.20.Dk	Measurement and error theory

Select this Article

Rolling Motion of a Ball Spinning About a Near-Vertical Axis

Rod Cross

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 25

Full Text: Read Online (HTML) | Download PDF

Show Abstract

A ball that is projected forward without spin on a horizontal surface will slide for a short distance before it starts rolling. Sliding friction acts to decrease the translation speed v and it acts to increase the rotation speed ω. When v = Rω, where R is the ball radius, the ball will start rolling and the friction force drops almost to zero since the contact point at the bottom of the ball comes to rest on the surface. The coefficient of rolling friction is much smaller than that for sliding friction. A different situation arises if the ball is projected forward while it is spinning about a vertical or near vertical axis. The latter situation arises in many ball sports. It arises if a player attempts to curve a ball down a bowling alley,¹ or when a billiards player imparts sidespin or “English” to a ball,² and it can arise in golf if a player strikes a ball with a putter at a point well away from the middle of the putter head. The situation also arises in the game of curling,³ although in that case the object that is projected is a cylindrical rock rather than a spherical ball, and it arises in tennis when a ball lands on the court spinning about a near vertical axis, as it does in both a slice serve and a kick serve. In a slice serve, the axis is almost vertical. In a kick serve, the axis is tilted about 30 degrees away from the vertical in order to increase the amount of topspin.⁴

Show PACS

01.50.My	Demonstration experiments and apparatus
46.55.+d	Tribology and mechanical contacts
45.40.Bb	Rotational kinematics

Select this Article

Removing the Mystery of Entropy and Thermodynamics — Part I

Harvey S. Left

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 28 | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract

Energy and entropy are centerpieces of physics. Energy is typically introduced in the study of classical mechanics. Although energy in this context can be challenging, its use in thermodynamics and its connection with entropy seem to take on a special air of mystery. In this five-part series, I pinpoint ways around key areas of difficulty to reduce that mystery. In Part I, the focus is on building an understanding of fundamental ideas of thermodynamics, including its connection with mechanics, and how entropy is defined and calculated. A central thread is that energy tends to spread within and between macroscopic objects, and this spreading is a surrogate for entropy increase. Specific questions are posed and answered, building on foundations laid in prior articles.^1–8 Parts II–V elaborate considerably on the ideas introduced here. A question-answer format is used throughout, with major results enumerated in Key Points 1.1–1.5.

Show PACS

01.50.-i	Educational aids
65.40.gd	Entropy

Select this Article

An Unexpected Heat Engine

K. P. Trout and Charles A. Gaston

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 32

Full Text: Read Online (HTML) | Download PDF

multimedia

Show Abstract

It's common knowledge that light can produce chemical and electronic changes (photography is based on those effects); however, many people consider light to have no mechanical effect. Some are familiar with the novelty of a radiometer that spins when placed in the light. Fewer are aware that a cymbal will vibrate audibly if hit by the light from a camera flash.¹ It came to our attention that the bubble in an ultra-sensitive level would move toward a flashlight beamed at the level from one end. Our investigations of this phenomenon show that it is thermal in nature and the effect large enough to be demonstrated in a classroom. With the addition of a small heating wire, the bubble level can be converted into a small heat engine.

Show PACS

01.50.My	Demonstration experiments and apparatus
07.20.Pe	Heat engines; heat pumps; heat pipes

Select this Article

Angular Acceleration Without Torque?

Richard D. Kaufman

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 35

Full Text: Read Online (HTML) | Download PDF

Show Abstract

Hardly. Just as Robert Johns qualitatively describes angular acceleration by an internal force in his article “Acceleration Without Force?”¹ here we will extend the discussion to consider angular acceleration by an internal torque. As we will see, this internal torque is due to an internal force acting at a distance from an instantaneous center.²

Show PACS

01.50.My	Demonstration experiments and apparatus
45.20.da	Forces and torques
45.20.df	Momentum conservation

Select this Article

Two Simple Activities to Bring Rainbows into the Classroom

Hakan Isik and Kemal Yurumezoglu

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 38

Full Text: Read Online (HTML) | Download PDF

Show Abstract

A rainbow reveals the colors of sunlight in a breathtaking way, but the formation of this natural event cannot be controlled by human beings. Transforming this out-of-class experience into a teaching activity is a challenge for science educators. This paper outlines two activities for rainbow formation in the science classroom in cases of good sunlight availability and artificial light.

Show PACS

01.50.My

Demonstration experiments and apparatus

Select this Article

Diurnal Astronomy: Using Sticks and Threads to Find Our Latitude on Earth

Néstor Camino and Alejandro Gangui

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 40

Online Publication Date: Dec 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract

It is well known that the length and orientation of a shadow cast by a vertical gnomon depends on the time of the day and on the season of the year. But it also depends on the latitude of the site of observation. During the equinoxes, the temporal sequence of the shadows cast by each of the points that form any object follows a straight line from west to east. A simple construction using sticks and threads can be used to materialize the plane of the celestial equators local projection, giving us a way to calculate our astronomical latitude during daytime with high precision.

Show PACS

01.50.My

Demonstration experiments and apparatus

Select this Article

Creativity and Introductory Physics

Ildefonso (Fonsie) J. Guilaran

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 42 | Cited 1 time

Full Text: Read Online (HTML) | Download PDF

Show Abstract

When I was an undergraduate physics major, I would often stay up late with my physics major roommate as we would digest the physics content we were learning in our courses and explore our respective imaginations armed with our new knowledge. Such activity during my undergraduate years was confined to informal settings, and the first formal creativity assignment in my physics education did not come until well into my graduate years when my graduate advisor demanded that I write a prospectus for my dissertation. I have often lamented the fact that the first formal assignment in which I was required to be creative, take responsibility for my own learning and research objectives, and see them to completion during my physics education came so late, considering the degree to which creative attributes are celebrated in the personalities of great physicists. In this essay I will apply some of the basic concepts as defined by creativity-related psychology literature to physics pedagogy, relate these concepts to the exchanges in this journal concerning Michael Sobel's paper¹ “Physics for the Non-Scientist: A Middle Way,” and provide the framework for a low-overhead creativity assignment that can easily be implemented at all levels of physics education.

Show PACS

01.50.-i

Educational aids

Select this Article

Using a High-Speed Camera to Measure the Speed of Sound

William Nathan Hack and William H. Baird

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 45

Full Text: Read Online (HTML) | Download PDF

Show Abstract

The speed of sound is a physical property that can be measured easily in the lab. However, finding an inexpensive and intuitive way for students to determine this speed has been more involved. The introduction of affordable consumer-grade high-speed cameras (such as the Exilim EX-FC100) makes conceptually simple experiments feasible. Since the Exilim can capture 1000 frames a second, it provides an easy way for students to calculate the speed of sound by counting video frames from a sound-triggered event they can see. For our experiment, we popped a balloon at a measured distance from a sound-activated high-output LED while recording high-speed video for later analysis. The beauty of using this as the method for calculating the speed of sound is that the software required for frame-by-frame analysis is free and the idea itself (slow motion) is simple. This allows even middle school students to measure the speed of sound with assistance, but the ability to independently verify such a basic result is invaluable for high school or college students.

Show PACS

01.50.My	Demonstration experiments and apparatus
43.58.Dj	Sound velocity

Select this Article

Helping Students to Think Like Scientists in Socratic Dialogue-Inducing Labs

Richard Hake

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 48

Full Text: Read Online (HTML) | Download PDF

Show Abstract

Socratic dialogue-inducing (SDI) labs^1,2 are based on Arnold Arons' half-century of ethnographic research, listening carefully to students' responses to probing Socratic questions on physics, science, and ways of thinking, and culminating in his landmark Teaching Introductory Physics.³ They utilize “interactive engagement” methods⁴ and are designed, in part, to help students think like scientists, e.g., to: (1) appreciate the need for operational definitions; (2) use and interpret pictorial, graphical, vectorial, mathematical, and written representations; and (3) consider dimensions, thought experiments, and limiting conditions. After giving some SDI lab examples from those categories, I conclude that the SDI lab attempts to help students think like scientists have been relatively successful.

Show PACS

01.50.Kw	Techniques of testing
01.50.My	Demonstration experiments and apparatus

Select this Article

The Numbers Speak: Physics First Supports Math Performance

Howard M. Glasser

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 53

Full Text: Read Online (HTML) | Download PDF

Show Abstract

More schools in the United States have begun teaching physics to ninth-graders, but there continues to be limited evidence that such a change benefits students.^1–2 Many arguments in favor of Physics First and the inverted sequence of physics-chemistry-biology^3–6 are based more on the intellectual logic of the sequence than on measured outcomes. Paul Lulai raised a similar concern in the November 2005 edition of The Physics Teacher, calling for “non-anecdotal evidence” that such a curricular change leads to various outcomes including “improved scores on standardized tests” and “improved mathematics understanding and achievement.”² This paper describes a study of a Physics First program at one school that suggests that this change to freshman physics positively impacted students' mathematical performance on standardized tests.

Show PACS

01.50.Kw

Techniques of testing

FERMI QUESTIONS

Select this Article FREE

Fermi Questions

Larry Weinstein, Column Editor

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 56

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable

Show PACS

04.70.-s

Physics of black holes

TRICK OF THE TRADE

Select this Article

Wavetank in a glass

Dave Van Domelen

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 56

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable

Show PACS

01.50.-i

Educational aids

PHYSICS CHALLENGE FOR TEACHERS AND STUDENTS

Select this Article FREE

Hot, cool, and working hard

Boris Korsunsky, Column Editor

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 57

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable

Show PACS

01.50.-i	Educational aids
07.20.Pe	Heat engines; heat pumps; heat pipes

YOUTUBE PHYSICS

Select this Article

Circular motion

Diane Riendeau, Column Editor

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 58

Full Text: Read Online (HTML) | Download PDF

Abstract Unavailable

Show PACS

01.50.Kw	Techniques of testing
45.40.-f	Dynamics and kinematics of rigid bodies

FOR THE NEW TEACHER

Select this Article

Insider conference tips

Jill Tennant

The Physics Teacher -- January 2012 -- Volume 50, Issue 1, pp. 59 | Cited 1 time

Full Text: Read Online (HTML) | Download PDF

Show Abstract

Attending an educator conference and its associated exhibit hall can be a rewarding experience for your brain. But if you keep in mind these insider's tips, your feet, arms, stomach, and wallet will also thank you.

Show PACS

01.50.-i

Educational aids