Understandings:
PS3.A: Definitions of Energy
1. Motion energy is properly called kinetic energy; it is proportional to the mass of the moving object and grows with the square of its speed. (MS-PS3-1)
2. A system of objects may also contain stored (potential) energy, depending on their relative positions. (MS-PS3-2)
3. Temperature is a measure of the average kinetic energy of particles of matter. The relationship between the temperature and the total energy of a system depends on the types, states, and amounts of matter present. (MS-PS3-3),(MS-PS3-4)
PS3.B: Conservation of Energy and Energy Transfer
1. When the motion energy of an object changes, there is inevitably some other change in energy at the same time. (MS-PS3-5)
2. The amount of energy transfer needed to change the temperature of a matter sample by a given amount depends on the nature of the matter, the size of the sample, and the environment. (MS-PS3-4)
3. Energy is spontaneously transferred out of hotter regions or objects and into colder ones. (MS-PS3-3)
PS3.C: Relationship Between Energy and Forces
1. When two objects interact, each one exerts a force on the other that can cause energy to be transferred to or from the object. (MS-PS3-2)
ETS1.A: Defining and Delimiting an Engineering Problem
1. The more precisely a design task’s criteria and constraints can be defined, the more likely it is that the designed solution will be successful. Specification of constraints includes consideration of scientific principles and other relevant knowledge that is likely to limit possible solutions. (secondary to MS-PS3-3)
ETS1.B: Developing Possible Solutions
1. A solution needs to be tested, and then modified on the basis of the test results in order to improve it. There are systematic processes for evaluating solutions with respect to how well they meet criteria and constraints of a problem. (secondary to MS-PS3-3)
Content Goals:
1. When the arrangement of objects interacting at a distance changes, different amounts of potential energy are stored in the system.
2. Devices that either minimizes or maximizes thermal energy transfer.* [Clarification Statement: Examples of devices could include an insulated box, a solar cooker, and a Styrofoam cup.] [Assessment Boundary: Assessment does not include calculating the total amount of thermal energy transferred.]
3. Relationships among the energy transferred, the type of matter, the mass, and the change in the average kinetic energy of the particles as measured by the temperature of the sample.
4. When the kinetic energy of an object changes, energy is transferred to or from the object.
5. Describe the relationships of kinetic energy to the mass of an object and to the speed of an object.
