Recently, there are two papers from Physical Review which suggest
utilizing energy-as-substance conceptual metaphor to help introductory
physics students to understand energy conservation, storage, and
1. Eric Brewe (2011). Energy as a substancelike quantity that flows:
Theoretical considerations and pedagogical consequences. Phys. Rev. ST
Physics Ed. Research. 7(2), 020106.
You may download the paper from this website: http://prst-per.aps.org/
2. Rachel E. Scherr, Hunter G. Close, Sarah B. McKagan, and Stamatis
Vokos (2013). Representing energy. I. Representing a substance
ontology for energy. Phys. Rev. ST Physics Ed. Research.
There are two questions:
1. If an object has more kinetic energy, it will have more substance,
and thus more mass?
2. The best universities may still prefer to introduce energy as
abstract quantity instead of energy-as-substance. Perhaps, some
"smarter" students in less competitive universities may feel unhappy
that inaccurate definition of energy is introduced in their curriculum?