Session B17: New Technologies & Resources for Teaching Undergraduate Physics

Re-visiting the measurement of the Speed of Sound in Air

Measuring the speed of sound in air is among the experiments conducted in introductory physics laboratory courses. Purpose of this re-visit is to improve accuracy with the use of current technologies in data collection. In the classic resonance-tube method, a tuning fork of known frequency and adjustable water level with a reservoir can (or other means) are used and the resonance condition is obtained by hearing the sound when it is loud. Instead, a speaker driven by a function generator and a sound sensor can be employed for more accurate results, where the resonance condition is obtained by means of the FFT display of the sound sensor. Here, eyes are used in addition to the ears to locate the resonance condition accurately. A magnifying glass is used to measure the meniscus of the water level. In addition, the sound sensor can be used in the echo method, where a PVC pipe (length = 1.52 m and diameter = 2.5 cm) closed on one end is used, and the time for echo is measured using the data collection software. In this method, a sound pulse is created by snapping the fingers close to the sound sensor, which is held at the open end of the pipe. Resulting multiple echoes of the pulses and their phase changes due to reflection are used in finding the travel time for an echo accurately. Accepted value is obtained using temperature, gas constant and ratio of specific heats and average molar mass for air, which is comparable within 1-2% of the measured values of the speed of sound in air using the resonance and echo methods.   

Grok Takes E&M Physics Exam

Can AI (artificial intelligence) and/or ML (machine learning) help students learn introductory physics? We recognize that Grok, ChatGPT, and the like, have the potential to dramatically change the landscape in our introductory physics courses. Many of the introductory physics textbook publishers are now looking at how to incorporate AI/ML into their educational materials. How can we, as instructors, incorporate AI/ML into our physics courses?

As a followup to previous work, where ChatGPT 3.5 took a physics exam in the algebra-based course on mechanics, here we have Grok-1 taking an exam in the algebra-based E&M physics. How good is Grok? I discuss how it performed on the exam, compare its score to the rest of the class (humans), and discuss some of the differences in Grok versus ChatGPT (in terms of their exam abilities).   

Are we selecting for or developing STEM interest and identity in out-of-school physics programs?

Decisions regarding whether or not to pursue science, technology, engineering, and mathematics (STEM) careers are made early in a youth’s education, as early as middle school. Thus, in order to attract youth into STEM fields, it is vital that the STEM Interest and positive STEM identity be fostered in elementary and middle (primary) school. One method for sparking interest STEM and fostering positive STEM identity is through informal STEM learning (ISL) experiences such as out-of-school programs, summer camps, etc. Though it is widely accepted in ISL communities that informal STEM learning increases participants’ STEM interest, and fosters positive STEM identity, it is unclear whether these experiences are successful in initiating STEM interest and STEM identity in youth who have no desire to pursue STEM careers. In this talk, we present findings of a study in which we examined differences in initial STEM interest and STEM identity among a group of primary school youth who participated in an out-of-school physics program, and primary youth who did not. Preliminary results suggest that participants had higher initial levels of STEM interest and STEM identity than non-participants. We discuss implications, limitations, and future directions of this work.