HS - PS3.A (A) - Defining Energy - FINAL (WND 4/16/2014)

Module: Defining Energy

DCI: PS3.A (A) Energy is a quantitative property of a system that depends on the motion and interactions of matter and radiation within that system. That there is a single quantity called energy is due to the fact that a system’s total energy is conserved, even as, within the system, energy is continually transferred from one object to another and between its various forms.

PE: HS-PS3-1 Create a computational model to calculate the change in the energy of one component in a system when the change in energy of the other component(s) and energy flows in and out of the systems are known.

[Clarification Statement: Emphasis is on explaining the meaning of mathematical expressions used in the model.] [Assessment Boundary: Assessment is limited to basic algebraic expressions or computations; to systems of two or three components; and to thermal energy, kinetic energy, and/or the energies in gravitational, magnetic, or electric fields.]

PE: HS-PS3-2 Develop and use models to illustrate that energy at the macroscopic scale can be accounted for as a combination of energy associated with the motions of particles (objects) and energy associated with the relative positions of particles (objects).

[Clarification Statement: Examples of phenomena at the macroscopic scale could include the conversion of kinetic energy to thermal energy, the energy stored due to position of an object above the earth, and the energy stored between two electrically-charged plates. Examples of models could include diagrams, drawings, descriptions, and computer simulations.]

The ideas are: 

- energy is a quantitative property

- The amount of energy in a system depends on the motion and interactions of matter and radiation taking place within that system. 

- A singular quantity of energy can be calculated due to the fact that the total energy in a system is conserved

- energy is conserved as it is continually transferred from one object to another or from one form to another

The first PE tells us that students should be able to explain mathematical reasoning.  We may be able to do something as similar as provide known quantities of potential energy entering within a system and then asking how to determine the amount of kinetic energy. 

The second PE can be addressed by asking students to explain how to calculate the total energy of a system, or can be very generalized as well.