The abstract nature of electric potential difference (voltage) can make it a difficult concept to grasp, but understanding the relative nature of voltage is central to developing a conceptual understanding of electric circuits. In laboratory situations, I see these conceptual difficulties manifest when students have difficulty placing voltmeter…

Alternative energy sources have become increasingly important as the production of domestic oil has declined and dependence on foreign oil has increased. Historically, there have been four time periods during which the United States was in fact crippled by oil shortages. These time periods include: (1) the early 1900s; (2) World War II; (3) the…

Criticizes a proposed approach to teaching physics in terms of energy carriers (SE 532 196), arguing that it requires energy to be thought of as a substance which can flow. Discusses problems related to concept formation and logical difficulties with the curriculum, considering several contradictions to physics principles which may arise. (JM)