MS-PS3-1: Construct and interpret graphical displays of data to describe the relationships of kinetic energy to the mass of an object and to the speed of an object.

Clarification Statement: Emphasis is on descriptive relationships between kinetic energy and mass separately from kinetic energy and speed. Examples could include riding a bicycle at different speeds, rolling different sizes of rocks downhill, and getting hit by a wiffle ball versus a tennis ball.

By the end of grade 8. 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. A system of objects may also contain stored (potential) energy, depending on their relative positions. For example, energy is storedin gravitational interaction with Earthwhen an object is raised, and energy is released when the object falls or is lowered. Energy is also stored in the electric fields between charged particles and the magnetic fields between magnets, and it changes when these objects are moved relative to one another. Stored energy is decreased in some chemical reactions and increased in others. The term “heat" as used in everyday language refers both to thermal energy (the motion of atoms or molecules within a substance) and energy transfers by convection, conduction, and radiation (particularly infrared and light). In science, heat is used only for this second meaning; it refers to energy transferred when two objects or systems are at different temperatures. 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-PS3-5: Construct, use, and present arguments to support the claim that when the kinetic energy of an object changes, energy is transferred to or from the object.

Clarification Statement: Examples of empirical evidence used in arguments could include an inventory or other representation of the energy before and after the transfer in the form of temperature changes or motion of object.

By the end of grade 8. When the motion energy of an object changes, there is inevitably some other change in energy at the same time. For example, the friction that causes a moving object to stop also results in an increase in the thermal energy in both surfaces; eventually heat energy is transferred to the surrounding environment as the surfaces cool. Similarly, to make an object start moving or to keep it moving when friction forces transfer energy away from it, energy must be provided from, say, chemical (e.g., burning fuel) or electrical (e.g., an electric motor and a battery) processes. 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. Energy is transferred out of hotter regions or objects and into colder ones by the processes of conduction, convection, and radiation.

Evidence Statements

MS-PS3-1

1. Organizing data

   1. Students use graphical displays to organize the following given data:

      1. Mass of the object.

      2. Speed of the object.

      3. Kinetic energy of the object.

   2. Students organize the data in a way that facilitates analysis and interpretation.

2. Identifying relationships

   1. Using the graphical display, students identify that kinetic energy:

      1. Increases if either the mass or the speed of the object increases or if both increase.

      2. Decreases if either the mass or the speed of the object decreases or if both decrease.

3. Interpreting data

   1. Using the analyzed data, students describe:

      1. The relationship between kinetic energy and mass as a linear proportional relationship (KE= m) in which:

         1. The kinetic energy doubles as the mass of the object doubles.

         2. The kinetic energy halves as the mass of the object halves.

      2. The relationship between kinetic energy and speed as a nonlinear (square) proportional relationship (KE= v2) in which:

         1. The kinetic energy quadruples as the speed of the object doubles.

         2. The kinetic energy decreases by a factor of four as the speed of the object is cut in half.

MS-PS3-5

1. Supported claims

   1. Students make a claim about a given explanation or model for a phenomenon. In their claim, students include the idea that when the kinetic energy of an object changes, energy is transferred to or from that object.

2. Identifying scientific evidence

   1. Students identify and describe the given evidence that supports the claim, including the following when appropriate:

      1. The change in observable features (e.g., motion, temperature, sound) of an object before and after the interaction that changes the kinetic energy of the object.

      2. The change in observable features of other objects or the surroundings in the defined system.

3. Evaluating and critiquing the evidence

   1. Students evaluate the evidence and identify its strengths and weaknesses, including:

      1. Types of sources.

      2. Sufficiency, including validity and reliability, of the evidence to make and defend the claim.

      3. Any alternative interpretations of the evidence and why the evidence supports the given claim as opposed to any other claims.

4. Reasoning and synthesis

   1. Students use reasoning to connect the necessary and sufficient evidence and construct the argument. Students describe a chain of reasoning that includes:

      1. Based on changes in the observable features of the object (e.g., motion, temperature), the kinetic energy of the object changed.

      2. When the kinetic energy of the object increases or decreases, the energy (e.g., kinetic, thermal, potential) of other objects or the surroundings within the system increases or decreases, indicating that energy was transferred to or from the object.

   2. Students present oral or written arguments to support or refute the given explanation or model for the phenomenon.

MS-PS3-1: Construct and interpret graphical displays of data to describe the relationships of kinetic energy to the mass of an object and to the speed of an object.

Clarification Statement: Emphasis is on descriptive relationships between kinetic energy and mass separately from kinetic energy and speed. Examples could include riding a bicycle at different speeds, rolling different sizes of rocks downhill, and getting hit by a wiffle ball versus a tennis ball.

By the end of grade 8. 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. A system of objects may also contain stored (potential) energy, depending on their relative positions. For example, energy is storedin gravitational interaction with Earthwhen an object is raised, and energy is released when the object falls or is lowered. Energy is also stored in the electric fields between charged particles and the magnetic fields between magnets, and it changes when these objects are moved relative to one another. Stored energy is decreased in some chemical reactions and increased in others. The term “heat" as used in everyday language refers both to thermal energy (the motion of atoms or molecules within a substance) and energy transfers by convection, conduction, and radiation (particularly infrared and light). In science, heat is used only for this second meaning; it refers to energy transferred when two objects or systems are at different temperatures. 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-PS3-5: Construct, use, and present arguments to support the claim that when the kinetic energy of an object changes, energy is transferred to or from the object.

Clarification Statement: Examples of empirical evidence used in arguments could include an inventory or other representation of the energy before and after the transfer in the form of temperature changes or motion of object.

By the end of grade 8. When the motion energy of an object changes, there is inevitably some other change in energy at the same time. For example, the friction that causes a moving object to stop also results in an increase in the thermal energy in both surfaces; eventually heat energy is transferred to the surrounding environment as the surfaces cool. Similarly, to make an object start moving or to keep it moving when friction forces transfer energy away from it, energy must be provided from, say, chemical (e.g., burning fuel) or electrical (e.g., an electric motor and a battery) processes. 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. Energy is transferred out of hotter regions or objects and into colder ones by the processes of conduction, convection, and radiation.

Evidence Statements

MS-PS3-1

1. Organizing data

   1. Students use graphical displays to organize the following given data:

      1. Mass of the object.

      2. Speed of the object.

      3. Kinetic energy of the object.

   2. Students organize the data in a way that facilitates analysis and interpretation.

2. Identifying relationships

   1. Using the graphical display, students identify that kinetic energy:

      1. Increases if either the mass or the speed of the object increases or if both increase.

      2. Decreases if either the mass or the speed of the object decreases or if both decrease.

3. Interpreting data

   1. Using the analyzed data, students describe:

      1. The relationship between kinetic energy and mass as a linear proportional relationship (KE= m) in which:

         1. The kinetic energy doubles as the mass of the object doubles.

         2. The kinetic energy halves as the mass of the object halves.

      2. The relationship between kinetic energy and speed as a nonlinear (square) proportional relationship (KE= v2) in which:

         1. The kinetic energy quadruples as the speed of the object doubles.

         2. The kinetic energy decreases by a factor of four as the speed of the object is cut in half.

MS-PS3-5

1. Supported claims

   1. Students make a claim about a given explanation or model for a phenomenon. In their claim, students include the idea that when the kinetic energy of an object changes, energy is transferred to or from that object.

2. Identifying scientific evidence

   1. Students identify and describe the given evidence that supports the claim, including the following when appropriate:

      1. The change in observable features (e.g., motion, temperature, sound) of an object before and after the interaction that changes the kinetic energy of the object.

      2. The change in observable features of other objects or the surroundings in the defined system.

3. Evaluating and critiquing the evidence

   1. Students evaluate the evidence and identify its strengths and weaknesses, including:

      1. Types of sources.

      2. Sufficiency, including validity and reliability, of the evidence to make and defend the claim.

      3. Any alternative interpretations of the evidence and why the evidence supports the given claim as opposed to any other claims.

4. Reasoning and synthesis

   1. Students use reasoning to connect the necessary and sufficient evidence and construct the argument. Students describe a chain of reasoning that includes:

      1. Based on changes in the observable features of the object (e.g., motion, temperature), the kinetic energy of the object changed.

      2. When the kinetic energy of the object increases or decreases, the energy (e.g., kinetic, thermal, potential) of other objects or the surroundings within the system increases or decreases, indicating that energy was transferred to or from the object.

   2. Students present oral or written arguments to support or refute the given explanation or model for the phenomenon.