Comments on Contextual Dimensions of the Energy Concept and

Implications for Goals of Energy Teaching and Learning, by Xiufeng Liu and Mihwa Park

Andy AndersonMichigan State University

Two Main Themes in Paper

1. Ontogeny and philogeny: parallels between historical development of the scientific energy concept and individual learning about energy. (Not really possible to add meaningfully to this discussion in a few pages, so I would recommend that it be taken out of the paper.)

2. Energy in three contexts:a. General cultural contextb. Scientific contextc. Economic political context

Energy in Cultural Context: Synonyms for Energy from Thesaurus.com

• Definition: person's spirit and vigor. Synonyms: activity, animation, application, ardor, birr, dash, drive, effectiveness, efficacy, efficiency, endurance, enterprise, exertion, fire, force, forcefulness, fortitude, get-up-and-go, go, hardihood, initiative, intensity, juice, life, liveliness, might, moxie*, muscle, operativeness, pep, pizzazz, pluck, potency, power, puissance, punch, spirit, spontaneity, stamina, steam, strength, toughness, tuck, vehemence, verve, vim, virility, vitality, vivacity, zeal, zest, zing, zip, élan

• Definition: generated power. Synonyms: application, burn, conductivity, current, dynamism, electricity, force, friction, gravity, heat, horsepower, juice, kilowatts, magnetism, potential, pressure, radioactivity, rays, reaction, response, service, steam, strength, voltage, wattage. (http://thesaurus.com/browse/energy)

Energy in Scientific Context (19th Century and NGSS version)

• Can be precisely measured in dimensions E = mass * distance2/time2

• Macroscopic: can take and be changed among different forms (kinetic, gravitational potential, thermal, etc.), but is always conserved

• Subatomic: [From the NGSS Framework, p. 123-4] “These relationships [among macroscopic forms of energy] are better understood at the microscopic scale, at which all of the different manifestations of energy can be modeled as either motions of particles or energy stored in fields (which mediate interactions between particles).”

• Second Law of Thermodynamics: Entropy increases in every process (so energy flows through systems rather than being cycled within them)

What Makes Energy a Powerful or Important Concept?

• Cultural power: multiplicity of meanings that have resonance in many different cultural contexts

• Scientific power: precise definitions that contribute to the predictive and explanatory power of scientific models

• These two kinds of power are inevitably in tension or in conflict

Energy in Economic/Political Context

• Essential commodity that is bought and sold• Comes from renewable or non-renewable

resources• Can be transferred or transformed many times

on the way to consumers, each time with some energy lost to inefficiency

• Is ultimately consumed/used up by consumers• Our need for energy drives pollution and

climate change

Question: What is the place for these three contexts for energy in the science curriculum?

My Answers• Understanding scientific context/uses of energy is

clearly our primary goal• We need to help students make clear distinctions

between scientific contexts and more general cultural contexts (and learn to use only scientific meanings in scientific contexts)

• Energy in economic/political contexts– Fully reconcile economic/political and scientific

meanings, recognizing that economic/political energy is constrained by scientific laws

– Avoid cultural meanings that are incompatible with scientific laws