Gained in Translation: The Sudden Pivot Taking Physics Labs to the Cloud as a Reform Opportunity

I will report on a positive experience with using the forced transition to online learning as an opportunity to adopt one of many best-practice examples from the world of Physics Education Research. Following the example in Developing scientific decision making by structuring and supporting student agency by N.G. Holmes, et al [1], (and the instructional materials shared on Physport.org), my efforts were directed toward cueing students to make decisions to design their research question during our online meetings, rather than developing materials to micro-manage their behaviors. Characteristics of the new online medium influenced instructional design and accessibility in surprising ways. The centrality of group scientific presentation to their peers prompted responses such as for the first time, I actually cared what the answer was.” Students participated in a belonging intervention,” and what was once their least-favorite class became a refuge of supportive relationships during a difficult time. How can we make that the new normal for physics lab? \\ N.G. Holmes, Benjamin Keep, and Carl E. Wieman, Phys. Rev. Phys. Educ. Res. 16, 010109 (2020

Quantifying Measurement Error in Digital Instruments

A first lab experiment clearly illustrates that a glucose meter is actually an excellent source of both random and systematic error, much to the surprise to students and physicians alike. A histogram is constructed and the utility of the standard deviation and standard error to quantify the uncertainty in each measurement and in the mean value, respectively, is demonstrated. From the first lab on, students are challenged to express and interpret confidence intervals in order to form quantitative conclusions. Assessments reveal that many students find this to be surprisingly challenging

The Physics of Human Performance: An IDEAL Lab

Physics lab goes to the gymnasium, where students calculate the mechanical power required to walk on an inclined treadmill in watts and convert to units power used to measure human performance: VO2, and METs. Students learn how to use two linear regression models: the ACSM walking equation to estimate the actual power expenditure of walking and the Rockport 1 mile test to estimate their own VO2max. Students use models to prescribe exercise parameters for themselves and for two cases. The IDEAL lab collaboration is developing labs that are open, applied to life, and rigorously quantitative

Above-threshold Ionization as Temporal Multi-slit Interference

When atoms are subjected to a laser pulse of sufficiently high intensity, electrons are ionized by absorbing multiple photons in excess of the ionization potential. The resulting sequence of peaks in the photoelectron spectrum separated by the energy of one photon is called ``above-threshold ionization\u27\u27 (ATI). This time-independent description of ATI invokes the language of photons, even though calculations are performed using the time-dependent Schrodinger equation with a classical electric field. We demonstrate that the energy-periodic structure of ATI can be understood from the interference of ionized electron wavepackets produced periodically each half-cycle of the laser field. Using this simple picture, rather analytic expressions for the ATI spectrum can be derived

Maybe I Could Use this Again! Two IDEAL Labs Introducing Instrumentation

Physics lab students are introduced to custom instrumentation using Arduino-like microcontrollers which have allowed us to implement two labs of particular utility for life-science majors. Constructing a fluid circuit using the sponge-resistor model, flow sensors and an LCD display show the current through each section of pipe. The instrument can simultaneously measure and record 18 voltages, which enables us to record high-frequency “snap shots” of a signal generated on an RC-circuit model of an axon. The IDEAL lab collaboration is developing labs that are open, applied to life, and rigorously quantitative

Including Wrist Flexion in the Human Arm Model Changes Everything!

Does your introductory physics laboratory experiment that analyzes the human arm as a lever assume an inflexible wrist? If so, the analysis of the biceps force required to perform a biceps curl will lead to results that contradict experience: one does not expect the required biceps force to decrease as the mass is raised. We will show that allowing for wrist flexion leads to agreement with empirical data: that the required force does increase as the mass is raised if the wrist angle is allowed to be optimal

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Giving students agency increased engagement at just the right time

Following the example in Developing scientific decision making by structuring and supporting student agency by N.G. Holmes, et al, students designed the research question in a three-week sequence and a written lab report was replaced with an online synchronous oral lab report, followed by time for questions from student colleagues. I will report on enhanced student engagement in class and in office hours and will share anecdotal comments. Students participated in a belonging intervention . I will share practical lessons learned

Immediacy by Design: Light Boarding, Streaming, and Recording Engaging Assets

A full-featured AV setup for a lightboard lecture capture system is presented that adds new features and at a dramatically-lower cost (using a Raspberry Pi, an HDMI switcher, and a Stream Deck macro keyboard). A teacher can, for instance, annotate transparent Power Point slides. Similar techniques can be adapted to capture screencasts that are more engaging without the need for post-production work

Above-threshold Ionization as Temporal Multi-slit Interference

When atoms are subjected to a laser pulse of sufficiently high intensity, electrons are ionized by absorbing multiple photons in excess of the ionization potential. The resulting sequence of peaks in the photoelectron spectrum separated by the energy of one photon is called ``above-threshold ionization\u27\u27 (ATI). This time-independent description of ATI invokes the language of photons, even though calculations are performed using the time-dependent Schr\ odinger equation with a classical electric field. We demonstrate that the energy-periodic structure of ATI can be understood from the interference of ionized electron wavepackets produced periodically each half-cycle of the laser field. Using this simple picture, rather analytic expressions for the ATI spectrum can be derived