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Predict the resulting motion of a system after applying external forces on the system, including friction (e.g. book on a table, an object being pushed across a floor, an accelerating car).

Unpacked Content

Scientific and Engineering Practices

Planning and Carrying out Investigations

Crosscutting Concepts

Energy and Matter


Students know:
  • Energy cannot be created or destroyed, but it can be transported from one place to another and transferred between systems.
  • Properties of materials cause different materials to absorb and release energy differently.
  • Conduction, convection, and radiation are methods of energy transfer.
  • Energy can be conserved when there are changes in potential, kinetic, or heat energy.


Students are able to:
  • Compare thermal energy, heat, and temperature.
  • Compare scenarios in which work is done and explain the differences in magnitude of work done using the relationship W=FΔd
  • Infer the ability of various materials to absorb or release thermal energy in order to relate mass, specific heat capacity and temperature of materials to the amount of heat transferred (q=mCΔT).
  • Relate phase changes to latent heat that changes the potential energy of particles while the average kinetic energy of particles (temperature) remains the same.
  • Compare conduction, convection, and radiation as methods of energy transfer.
  • Exemplify the relationships between kinetic energy, potential energy, and heat to illustrate that total energy is conserved in mechanical systems such as a pendulum, roller coaster, carts/balls on ramps.
  • Relate types of friction in a system to the transformation of mechanical energy to heat.
  • Explain scenarios in which work is done identifying the force, displacement, and energy transfer. (When work is done on an object, the result is an increase in its energy and is accompanied by a decrease in energy elsewhere.)


Students understand that:
  • Conservation of energy means that the total change of energy in any system is always equal to the total energy transferred into or out of the system.


  • System
  • Energy
  • Mechanical
  • Temperature
  • Conduction
  • Convection
  • Radiation
  • Friction
  • Force
  • Specific heat capacity
  • Latent heat
  • Heat of vaporization
  • Law of Conservation of energy
  • Transformation
  • Potential energy
  • Kinetic energy
  • Thermal energy
  • Heat
  • Work
  • Phase changes