Editor selections by Topic and Unit

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## Physics First:Measurement and the Language of Physics Units

This topic contains a selection of units designed to help you to teach physics. In physics, using precise measurements and standard units is important in comparing physical quantities and understanding basic concepts.

### Frames of Reference (1)

#### Activities:

This animation takes the fear out of reference frames, and it's fun. All motion is relative to a frame of reference. This resource shows how the motion of a bouncing basketball looks different depending on whether the observer is standing still, walking in the same direction as the player, or walking in the opposite direction. It offers students nine scenarios (frames of reference), and they must answer questions from the observer's viewpoint.

Item Type: Interactive Animation
Duration: 20 minutes

### Physics Terminology (2)

#### Activities:

If you've never visited the award-winning Hyperphysics web site, put it on your list. It is a set of online tutorials that features concept maps laid out in a web-like fashion for easy navigation. This page describes units of measurement, unit conversions, dimensional analysis, and basic mechanical quantities. Some of the maps are "active graphics", which link to capsules of background information. Remarkably easy to use!

Item Type: Reference Material
Level: Teacher Support

#### Student Tutorials:

To a beginning student, the unfamiliar language of physics can seem like a foreign tongue. This tutorial, part of the respected Physics Classroom collection, is an interactive introduction to some basic terminology. It focuses on scalars, vectors, distance, and displacement.

Item Type: Interactive Tutorial
Duration: 30 minutes

### Units of Measure (4)

#### Activities:

This resource is a digital tool for performing unit conversions with the extra feature of displaying cancellation of terms, helping students to gain a deeper understanding of the mathematical processes involved.  Students can convert among 25 physical quantities, including units such as force, temperature, energy, and current.

Item Type: Mathematical Tool

#### References and Collections:

All mechanical quantities can be expressed in terms of three quantities: length, mass, and time. This resource from Hyperphysics describes units of measurement, unit conversions, dimensional analysis, and basic mechanical quantities. Some of the maps are "active graphics", which link to capsules of background information. Remarkably easy to use!

Item Type: Reference Material
Level: High School

NIST, the National Institute of Standards and Technology, publishes this set of in-depth reference materials, covering 3 topics:  1) Fundamental physical constants, 2) International System of Units (SI), and 3) Uncertainty in measurement.

Item Type: Reference Material
Level: Teacher Support

Teachers will find in-depth information on base units, derived units, and relationships among SI units in this free web site developed and maintained by NIST (the National Institute for Science and Technology). Don't miss the link to the "Digital Dutch" unit converter.  It is amazingly easy to use.

Item Type: Reference Material
Level: Teacher Support

### Applying Measurement in Physics (12)

#### Lesson Plans:

This 3-day inquiry-based lesson is a great way for students to discover what "accuracy" and "precision" mean in measurement. Fun hands-on activities include measuring objects using ancient "cubit" units and tossing foam darts to gather data. The lesson concludes as students work cooperatively to explore using significant figures. Includes analysis questions and data tables.

Item Type: Cooperative Learning
Duration: 3 class periods

This fun lesson lets students explore a real-life scenario as they compare volume for a cylinder (round hay bale) and a rectangular prism (box-shaped hay bale). They will use math to decide why one shape of hay bale is preferable economically to the other. But wait.....the round bales don't fit in a barn as well, which could affect the outcome of the problem!

Item Type: Lesson Plan
Duration: 45 minutes

One of the best lessons we've found to help students get the connection between dimension and volume. They conduct an experiment to create two rectangular prisms and two cylinders, then determine which design holds the most popcorn. They will test ideas, graph outcomes, and present findings. Includes printable worksheets with answer keys.

Item Type: Experiment
Duration: 2 Class Periods

An exceptional resource collection on how to integrate "direct measurement videos". These high-speed short videos feature tools for easy analysis of various physical situations:  rulers, grids, frame-counters, and screen overlays for making precise measurements. Includes 20+ teaching modules with lesson plans, assessments and answer keys, and pedagogical background. Does not require purchase or installation of video analysis software.

Item Type: Video Analysis Lessons

#### Activities:

This free digital grapher is especially user-friendly for beginning learners. Students can choose from five graph types: bar, line, area, pie, and X/Y.  Various patterns, colors, grids, and label choices are available to allow customization. Minimum and maximum values can be set to limit the scale of the graph.

Item Type: Graph-Making Tool

After introducing the rules of significant figures, students can test their skills in this interactive drill & skill. We suggest setting up cooperative learning groups to make it a game.  NOTE FROM THE EDITOR: beginning students often misunderstand or overestimate the usefulness of significant figures. In real-world research laboratories, practicing scientists commonly express uncertainty quantities as a separate numeral. Good examples of how to express uncertainty can be found in the NIST Fundamental Physical Constants (Reference below).

Item Type: Problem Set
Level: High School
Duration: 30 minutes

This is a really nice interactive simulation to give students virtual practice in using a micrometer, a device for doing ultra-precise measurement down to the level of 1 micrometer. Each time the "reset" button is pressed, a random-size object appears on screen. Students use sliders to move the object into place, perform the measurement, and check the accuracy of their reading.

Item Type: Interactive Simulation
Duration: 30 minutes

This Java-based activity lets students manipulate a 3-D rectangular prism or triangular prism to explore surface area and volume. It's designed to help secondary students visualize the relationship of width, depth, and height in calculating and estimating volume/surface area.

Item Type: Interactive Simulation
Duration: 30 minutes

#### References and Collections:

Values of the fundamental physical constants, recommended for international use, are provided at this web site. These are the latest values of the constants recommended by CODATA.  Need background information?  It's all there, in an easily-searchable format. Note: CODATA adjustment based on the recently revised SI is under review in 2018. By 12/31/2018, changes will be made that will significantly affect the uncertainties of many constants.

Item Type: Reference Material

#### Content Support For Teachers:

Accurate measurement is important in physical science, but no measurement is absolutely precise. If we assign any two people to measure the same object, there will always be a slight difference.....even if it's only a fraction of a centimeter. In physical science, this is called "uncertainty". This is a great resource to help teachers and students understand the role of error in measurement and how it can affect the results of an experiment.

Item Type: Online Tutorial
Level: Teacher Support

#### Student Tutorials:

Measurement of physical objects is, by nature, imprecise. When rounding numbers, you must use enough digits to minimize errors.  However, if too many digits are used, errors can be easily made keeping track of all the numerical values. This tutorial will help students with the basic rules.

Item Type: Interactive Tutorial
Level: High School
Duration: 30 minutes

Converting between units doesn't have to be frustrating to your students. This tutorial, part of an award-winning collection, is the best we found for demonstrating how to use unit cancellation to solve problems involving unit conversions.

Item Type: Online Tutorial

### For the New Teacher (4)

#### Activities:

This digital unit converter offers students more than the typical online conversion resource.  It allows conversion among 25 physical quantities, from more common applications (force, energy, current, voltage) to lesser-used conversions such as illuminance and magnetic flux.  It provides the additional feature of displaying cancellation of terms, helping beginners to gain a deeper understanding of the mathematical processes involved.

Item Type: Mathematical Tool

#### References and Collections:

This site is designed to be a resource for learning introductory level, algebra based, physics.  Lessons and review are organized by topic. The collection features an especially robust section on Units, Measurement, Significant Figures, and use of measurement tools. A \$5.00 annual fee gives teachers access to additional simulations, many of which have been rewritten to HTML5.

Item Type: Tutorial Collection
Level: High School Physics

This resource is a comprehensive guide on SI for teachers and students.  It contains tables, charts, and text explanations of base units, derived units, equivalencies, common quantities, and prefixes.  To aid the learner in visualizing quantities, drawings of common multiples are provided for each of the base units.  The materials are written so that a user with no prior experience with metrics can comprehend the measurements and how they are applied mathematically.

Item Type: Reference Material
Level: Teacher Support

#### Content Support For Teachers:

This item, part of the Open Door website, discusses the role of uncertainty in measurement.  Review the difference between systematic and random error, and gain practice in quantifying the error.  Also find high-quality sections on the Vernier scale, "best-fit line", and sampling frequency.

Item Type: Online Tutorial
Level: Teacher Support

### Teaching Tools (4)

#### Activities:

This is a very easy to use digital tool for performing unit conversions with the extra feature of displaying cancellation of terms, helping students to gain a deeper understanding of the mathematical processes involved.  Students can convert among 25 physical quantities, including units such as force, temperature, energy, and current.

Item Type: Mathematical Tool

This free digital grapher is especially user-friendly for beginning learners. Students can choose from five graph types: bar, line, area, pie, and X/Y.  Various patterns, colors, grids, and label choices are available to allow customization. Minimum and maximum values can be set to limit the scale of the graph.

Item Type: Graph-Making Tool

This beautifully designed version of Powers of 10 takes students on a "nano-journey" inside a carbon-based cell, an LED diode, and a laptop microchip. At each descending level, you can click on background information and additional Flash simulations. Kids can choose from 3 images and send "postcards" to friends about their journey. Flash must be enabled to run Nanoreisen. Even if you've begun to avoid Flash, you may want to make this resource your exception.

Item Type: Interactive Animation
Duration: One Class Period

#### Assessment:

Here is a set of free assessment tools for grades 6-12 on topics that cover force and motion, waves, properties of matter, and chemistry.  Diagnoser assessments are aligned with the NGSS, and include elicitation (warm-ups) and developmental lessons.  After completing the lesson, Diagnoser students answer digital question sets on specific topics, with immediate feedback provided to both teachers and learners. The final step in the process is "Prescriptive Activities", designed to target specific problematic areas located by Diagnoser.

Item Type: Assessment Tool

### Dimensional Analysis (3)

#### Content Support For Teachers:

This web page is part of the highly-regarded Hyperphysics concept maps. It describes units of measurement, unit conversions, dimensional analysis, and basic mechanical quantities. Some of the maps are "active graphics", which link to capsules of background information. Remarkably easy to use!

Item Type: Reference Material
Level: Teacher Support

#### Student Tutorials:

Dimensions of a quantity refer to the combination of units or base quantities that make it up. Most physical quantities can be expressed in terms of five basic dimensions and their combinations: mass, length, time, electrical current, and temperature. Often, students have difficulty understanding why dimensions are different than units. This tutorial contains basic information, 3 short quizzes and one longer post-test. Your students can move at their own pace or work in cooperative groups. **NOTE: This activity can be done without computers, as all components are printable.

Item Type: Instructional Module
Duration: 2-3 class periods

Your students will need to understand how to cancel units before they can solve problems using dimensional analysis. Beginning with simple one-step conversions, it progresses to problems requiring multiple conversions. Students will like the informal writing style by the author, whose motto is "If I can do this stuff, then so can you!"

Item Type: Online Tutorial

### Scale, Order of Magnitude, and Estimation (4)

#### Activities:

Students explore size estimation in 1, 2, and 3 dimensions. Multiple levels of difficulty allow for progressive skill improvement. Activity is great fun; expect students to be very engaged!

Item Type: Interactive Animation
Duration: One class period

An updated version of "Powers of 10".  View the Milky Way at 10 million light years from Earth, then move through space at successive orders of magnitude until you reach an oak tree in Florida. After than, move from a single leaf to the cell nucleus, chromatin, DNA, and subatomic particles.

Item Type: Image Set
Duration: 15 minutes

Interactively explore various specimens as they appear under a scanning electron microscope (SEM).  SEM can produce very high-resolution photos of details as small as 1-5 nanometers. Students can adjust the focus, brightness, and contrast, and choose from a cockroach, pollen grain, diatom, a gecko foot, a jellyfish, and more. Each successive image doubles the magnitude of the magnification.

Item Type: Images/Illustrations
Duration: 30 minutes

This beautifully designed version of Powers of 10 takes students on a "nano-journey" inside a carbon-based cell, an LED diode, and a laptop microchip. At each descending level, you can click on background information and additional Flash simulations. Kids can choose from 3 images and send "postcards" to friends about their journey. Flash must be enabled to run Nanoreisen. Even if you've begun to avoid Flash, you may want to make this resource your exception.

Item Type: Interactive Tutorial
Duration: One Class Period

### Assessments (3)

#### References and Collections:

The National Assessment of Educational Progress (NAEP) is the only nationally administered, continuing assessment of what America's students know and can do in various subject areas.  This website provides free access to the most recent assessment questions, organized by topic and level. Teachers can view an analysis of the results to see short-term and long-term trends in samples of students at ages 9, 13, or 17 years.

Item Type: Assessment Tool