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A two-axis solar tracker and its interactive kiosk were designed by an interdisciplinary team of students and faculty. The objective was to develop a publicly accessible kiosk that would facilitate the study of energy usage and production on campus. Tracking is accomplished by an open-loop algorithm, microcontroller, and ham radio rotator. Solar panel output is monitored in real time and displayed to the public with lights and digits that can be read by the casual passersby. While maximum power point tracking is the most accurate means of quantifying the output power of a photovoltaic panel, simplicity and design constraints dictated the use of short-circuit current as a proxy for power. A touchscreen display allows kiosk visitors to compare two solar panels, an automatic tracker that faces the sun, and an identical panel whose elevation and azimuth can be controlled with a virtual joystick. This project was a capstone experience for students in physics/engineering, computer science, and instructional technology. We discuss technical challenges and design choices, as well as the educational goals of the kiosk.

Force probes are versatile tools in the physics lab, but their internal workings can introduce artifacts when measuring rapidly changing forces. The Dual-Range Force Sensor by Vernier uses strain gage technology to measure force, based on the bending of a beam. Strain gages along the length of the beam change resistance as the beam bends. The elasticity of the beam leads to oscillations that persist after being excited by an impulsive force. How quickly the force probe freely returns to zero is thus related to the rigidity of the beam and the total mass attached to it. By varying the added mass and measuring the resulting frequency of the probe's internal free oscillations, the effective mass and spring constant of the probe's moveable parts can be found. Weighing of the probe parts and conducting a Hooke's law experiment provide static verification of these parameters. Study of the force sensor's behavior helps students to learn about damped harmonic motion, mathematical modeling, and the limitations of measuring devices.

Students can learn the Bernoulli principle of fluid pressure by looking at the mechanisms that operated the shut-off sensor in the nozzle of a gas pump.

An experiment to find out the energy changes between the plates of capacitor, under different conditions of constant charge and constant voltage are examined by using energy flow diagrams.

The history of the candela, which is one of the seven SI base units, its measurement techniques and its relation to the lumen are discussed. To find out the relationship, the luminous properties of incandescent and fluorescent lamps are compared.

The flow of water in a garden hose can help illustrate Isaac Newton's second law of motion. When both ends of the hose are stationary and water is flowing, moving the hose in the direction of the flow decreases flow rate, while moving the hose against the flow increases the flow rate. Scientific analysis of this phenomenon illustrates important physics principles.

The manner in which several light bulbs light up in a series circuit are examined, focusing on how lights burn at different brightness and illuminate at different times. Topics include the nature of a non-ohmic conductor and power dissipation within different resistors.

A low-friction rotating platform, sturdy enough to stand on and allow students to experience the conservation of angular momentum, can be constructed from motor vehicle water pump. The water pump does not pump anything, rather it substitutes as a commercial rotator at a fraction of the cost.