The Physics of Pool

The objective of this lesson is to illustrate how a common everyday experience (such as playing pool) can often provide a learning moment. In the example chosen, we use the game of pool to help explain some key concepts of physics. One of these concepts is the conservation of linear momentum since conservation laws play an extremely important role in many aspects of physics. The idea that a certain property of a system is maintained before and after something happens is quite central to many principles in physics and in the pool example, we concentrate on the conservation of linear momentum. The latter half of the video looks at angular momentum and friction, examining why certain objects roll, as opposed to slide. We do this by looking at how striking a ball with a cue stick at different locations produces different effects.

Material Type: Lecture

Author: Joseph A. Formaggio

The Physics Professor

This task requires students to answer questions about the structure of an expression.

Material Type: Activity/Lab

Author: Illustrative Mathematics

Pinhole Magnifier

In this activity related to light and perception, learners use a pinhole in an index card as a magnifying glass to help their eye focus on a nearby object. Learners will also discover that because this magnifier limits the amount of light that reaches their eye from the object, the pinhole makes the object appear dimmer. Learners are encouraged to explore using pins and needles with different diameters to make different-sized holes in index cards to see how this affects the image. They can also try forming a pinhole by curling their index finger.

Material Type: Activity/Lab

Plot the Dot

In this activity, learners work in groups to determine the mass and volume of four samples: glass marbles, steel washers or nuts, pieces of pine wood, and pieces of PVC pipe. Learners then plot the data points on a large class graph of mass vs. volume to discover that data points for a particular material form a straight line, the slope of which gives the density of the material.

Material Type: Activity/Lab

Authors: Don Rathjen, The Exploratorium

Polarized Sunglasses

In this activity, learners explore how polarizing sunglasses can help diminish road glare. By rotating a pair of polarizing sunglass lenses or other polarizing materials, learners will discover that some angles are better at reducing glare than others. Learners observe light from the sky, reflected from a mirror, or reflected from the surface of a pond. Use this activity to introduce learners to principles of light and polarization.

Material Type: Activity/Lab

Probability: Central limit theorem

After heuristically deriving Stirling's approximation in the first video segment, we outline a simple example of the central limit theorem for the case of the binomial distribution. In the final segment, we explain how the central limit theorem is used to suggest that physical experiments are characterized by normally-distributed (Gaussian) fluctuations while fluctuations in biological experiments are said to fill out log-normal distributions.

Material Type: Lecture Notes

Author: David Liao

Quantifying the Energy Associated with Everyday Things and Events

The topic of this video is energy in general, and specifically the ways we can quantify it. In order to make the concepts accessible to a broad audience, this video focuses on everyday things and events. How is it that energy plays a part in a child riding a scooter? How is the energy we consume in playing related to the energy on the food we eat? This video poses these questions to the class and challenges them to put a list of five such items into an ordering from most energy to least.

Material Type: Lecture

Author: Daniel D. Frey

Reading Guides for OpenStax College Physics

This resource consists of two .zip files that have reading guides for the College Physics textbook at openstax.org. Each zip file has Word documents for the standard first and second semester set of topics for a year-long freshman level college physics course. The reading guides summarize the key points, provide extra explanations, and pose questions for the student. The reading guides were written for the first edition of the textbook. Permission is granted for free use and editing of the reading guides.

Material Type: Full Course, Lecture Notes, Student Guide

Seasons and Shadows

In this activity you'll see how the sun's tilt on its axis changes the length of shadows. For example, why is your shadow longer in winter than in summer? It's easy to see the answer if you have a "sun" and an orbiting "earth" to demonstrate. Like many other ancient people, the ancient Chacoans used the annual changes in shadows to measure the passage of time and the change in seasons. You can too!

Material Type: Activity/Lab

Author: Linda Shore

Seeing Your Retina

In this quick optics activity, learners use a dim point of light (a disassembled Mini MagLite and dowel set-up) to cast a shadow of the blood supply in their retina onto the retina itself. This allows learners to see the blood supply of their retina and even their blind spot. Learners are encouraged to wear eye protection.

Material Type: Activity/Lab

A Simple Escapement Mechanism

In this activity, learners build a simple mechanism that regulates the "escape" of energy released by a falling weight by portioning it into discrete amounts. Escapements are found in mechanical clocks, such as those driven by a pendulum or a spring. Learners will build the wrapping form of escapement said to be used in a fifteenth-century German clock.

Material Type: Activity/Lab

Authors: Don Rathjen, The Exploratorium

Skateboard Science

This site from the Exploratorium looks at the physics of skateboard tricks (ollieing, mid-air maneuvers, and pumping for speed) and the physics of the skateboards themselves (wheels, bearings, trucks).

Material Type: Activity/Lab

Soap Bubbles

Learners explore three-dimensional geometric frames including cubes and tetrahedrons, as they create bubble wands with pipe cleaners and drinking straws. Then they investigate how soap film flows into a state of minimum energy when they lift the wand up from the bubble solution. Learners also see how light reflection and interference create shimmering colors in the bubbles.

Material Type: Activity/Lab

Soaring in The Wind: The Science of Kite Flying

Flying kites is a popular hobby in Malaysia and very much part of the culture. This lesson looks at kite flying science to introduce basic ideas related to the dynamics of kite flying and can be used as an extension of a physics lesson, especially after the students have learned about forces. It will focus on some of the concepts such as weight, thrust, lift and drag. It is a fun way to introduce the forces acting upon a kite and the scientific principles that allow a kite to fly. The lesson is suitable for students in secondary school. It will help students relate to the effect of forces and gives an introduction to the science of flight. As an added value, the video will also share some information about Malaysian kites which are “tailless”. The Malaysian kite is called “Wau” (pronounced “wow”), and there are many distinctive designs since each Malaysian state has its own official Wau. Malaysia has 14 states. The break activities included are to be conducted in the classroom, and students are to work in small groups on the questions given in the lesson. Students are to carry out two simple experiments to study how air flows on a kite.

Material Type: Lecture

Author: Roselainy Binti Abdul Rahman, Habibah Norehan Binti Hj Haron, Nor Azizi Binti Mohamed, Salwani Binti Mohd. Daud, Norzaida Binti Abas, Hafiza Binti Abas

Spherical Reflections

In this art meets science activity, learners pack silver, ball-shaped ornaments in a single layer in a box to create an array of spherical reflectors. Learners can use this as a tool to study the properties of spherical mirrors while creating colorful mosaic reflections. This is a great optics activity to use during the holiday season or any time of year.

Material Type: Activity/Lab

Stochasticity, a first introduction

Even when we model the dynamics of the abundances of molecules inside biological systems using calculus, it is important to remember that underlying behavior can be apparently random ("stochastic"). Even a deterministic system containing components moving in periodic ways can, at early times, support dynamics that appear disordered. The behavior of systems containing complicated collections of interacting parts can be difficult to predict with accuracy (chaos). Finally, systems can display stochasticity because the outcomes of measurements on quantum systems are indeterminate in a fundamental way. Random processes are modeled using Markov models.

Material Type: Lecture Notes

Author: David Liao

The Stroboscopic Effect

This module is about a particular effect of the frequency, which is the stroboscopic effect. The lesson discusses and demonstrates low frequency phenomena - less than 16 Hz - that can usually be observed clearly by the human eye, as well as high frequency phenomena - more than 25 Hz - that are difficult for the human eye to catch. This video also explores and demonstrates how high frequency phenomena can be observed by freezing the fast moving phenomena using a device called a stroboscope. The only prerequisite for this video is that students understand the definition of the frequency of a periodic phenomenon.

Material Type: Lecture

Author: Nawwaf Abu-Aqeel

tiny Pants Photo Challenge

In this activity, learners use basic measurements of the Earth and pieces of rock and iron to estimate the mass of the Earth. Learners will calculate mass, volume, and density, convert units, and employ the water displacement method. To calculate an even more accurate estimate of the mass of the Earth, this resource includes optional instructions on how to measure the iron core mass.

Material Type: Activity/Lab

Authors: Eric Muller, The Exploratorium

Touch the Spring

In this activity, a lightbulb is placed in front of a concave mirror. The actual lightbulb is not visible to the viewer, but the viewer can see the mirror image of the lightbulb formed in space. When the viewer tries to touch the lightbulb, they are attempting to touch an image. Their hand moves right through what seems to be a solid object! Learners will enjoy this illusion, while investigating principles of light and mirrors. In this version of a popular Exploratorium exhibit, a lightbulb is substituted for a spring.

Material Type: Activity/Lab

Uncertainty propagation: Curve fitting

Students will learn a sample-variance curve fitting method that can be used to determine whether a set of experimental data appears to have been generated by a model. This method is based on minimizing the reduced chi-squared value. This video includes a reminder to inspect normalized residuals before reporting fitted parameters.

Material Type: Lecture Notes

Author: David Liao