Powerbanks differ in the amount of energy they can store. Usually this capacity (in a colloquial sense) of the powerbanks is stated in the form of charge in mAh for effective advertising. From a physical point of view, shouldn't the energy that a powerbank can provide be of interest? For students, charging smartphones with power banks is…

Educating our future citizens in science and engineering is vitally important to ensure future advancement. Presently, in the light of environmental sustainability, it is critical that students learn concepts relating to energy, its consumption and future demands. In this article, we harness the state of the educational technology, namely…

A Genecon is an inexpensive hand-cranked dc electric generator. You can use it to charge a one-farad supercapacitor. If you stop cranking the handle, the capacitor will discharge, sending a current into the Genecon and thereby causing the handle to start turning as an electric motor. How does the current direction compare before and after you stop…

Harnessing energy from the tides is a much-promoted but rarely realised way of generating electricity. This article examines some of the systems that are currently in use or under development, and outlines their economic, environmental and technical implications.

The measurement of the force acting between two parallel, current-carrying wires is known as Ampère's experiment. A mechanical balance was historically employed to measure that force. We report a simple experiment based on an electronic precision balance that is useful in clearly showing students the existence of this interaction and how to…

We use a tablet to experimentally determine the dependencies of the magnetic field (B) on the electrical current and the axial distance from a coil (z). Our data shows good precision on the inverse cubic dependence of the magnetic field on the axial distance, B?z[superscript -3]. We obtain the value of air permeability µ[subscript air] with good…

A simple machine does one of two things: create a mechanical advantage (lever) or change the direction of an applied force (pulley). Fluid foils are unique among simple machines because they not only change the direction of an applied force (wheel and axle); they convert fluid energy into mechanical energy (wind and Kaplan turbines) or vice versa,…

People who live near wind turbines complain of symptoms that include some combination of the following: difficulty sleeping, fatigue, depression, irritability, aggressiveness, cognitive dysfunction, chest pain/pressure, headaches, joint pain, skin irritations, nausea, dizziness, tinnitus, and stress. These symptoms have been attributed to the…

We physics teachers are forever in search of real-life applications of the theoretical concepts we teach. In mechanics we often utilize vehicle motion exercises, yet most textbook problems involving these are rather tame and deal with constant acceleration. What often captures the imagination of students is the actual performance of cars they…

This article investigates the impacts of proper modeling of the wake effects and wind speed delays, between different wind turbines' rows, on the dynamic performance accuracy of the wind farms models. Three different modeling scenarios were compared to highlight the impacts of wake effects and wind speed time-delay models. In the first scenario,…

This module applies basic laws of thermodynamics to the study of the efficiency at which heat can be converted to other useful forms of energy, including heat at low temperatures. The module is divided into four major sections. Section I treats energy conversion efficiency and defines the concept of first-law efficiency, the most widely used…

Discusses the concepts of energy, flow of energy through ecosystems in which people live, our increasing use of energy as society evolves, and the importance of energy to all societies. A chart listing advantages/disadvantages of various energy sources is included. (JN)

Explains that the efficiency and the useful power available from a windmill turbine, of a laminar-flow model, will vary due to rotational kinetic energy of the downwind stream and turbulent mixing from outside the boundaries of the idealized stream. (GA)

Unified Technical Concepts (UTC) is a modular system for teaching applied physics in two-year postsecondary technician programs. This UTC laboratory textbook, the second of two volumes, consists of 45 learning modules dealing with basic concepts of physics. Addressed in the individual chapters of the guide are the following topics: force…

Four classroom activities are included in this 8-10 period unit suitable for high school chemistry and physics classes. The first activity is a reading (12th-grade readability level determined by the Fry procedure) which explains electricity conversion, transportation, and efficiency ratings. The second and third activities are electrical energy…