• Ask questions about data to determine the factors that affect the strength of electric and magnetic forces. (MS-PS2-3)

• Electric and magnetic (electromagnetic) forces can be attractive or repulsive, and their sizes depend on the magnitudes of the charges, currents, or magnetic strengths involved and on the distances between the interacting objects. (6-8)
• Attraction and repulsion between electric charges at the atomic scale explain the structure, properties, and transformations of matter, as well as the contact forces between material objects. (9-12)

• Patterns can be used to identify cause and effect relationships. (6-8)
• Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena. (9-12)

• Cause and effect relationships may be used to predict phenomena in natural systems. (6-8)
• Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system. (9-12)

• Complex and microscopic structures and systems can be visualized, modeled, and used to describe how their function depends on the relationships among its parts, therefore complex natural structures/systems can be analyzed to determine how they function. (6-8)

• Science assumes that objects and events in natural systems occur in consistent patterns that are understandable through measurement and observation. (6-8)
• Science assumes the universe is a vast single system in which basic laws are consistent. (9-12)

• Analyzing data in 6–8 builds on K–5 and progresses to extending quantitative analysis to investigations, distinguishing between correlation and causation, and basic statistical techniques of data and error analysis. (6-8)
  • Analyze and interpret data to provide evidence for phenomena. (6-8)
• Analyzing data in 9–12 builds on K–8 and progresses to introducing more detailed statistical analysis, the comparison of data sets for consistency, and the use of models to generate and analyze data. (9-12)
  • Analyze data using computational models in order to make valid and reliable scientific claims. (9-12)

• Modeling in 9–12 builds on K–8 and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed worlds. (9-12)
  • Use a model to predict the relationships between systems or between components of a system. (9-12)

• 6-8: 11B/M1. Models are often used to think about processes that happen too slowly, too quickly, or on too small a scale to observe directly. They are also used for processes that are too vast, too complex, or too dangerous to study.

• 4G (9-12) #3.  There are two kinds of charges?positive and negative. Like charges repel one another, opposite charges attract. In materials, there are almost exactly equal proportions of positive and negative charges, making the materials as a whole electrically neutral. Negative charges, being associated with electrons, are far more mobile in materials than positive charges are. A very small excess or deficit of negative charges in a material produces noticeable electric forces.

• 9-12: Motions & Forces

This set of three models would be a great choice for an inquiry-based exploration of electric field strength, attraction/repulsion between positive and negative charges, and factors that affect the direction of field lines. We recommend allowing one class period for students to explore the models before introducing labs on electrostatics. Each model includes accompanying problem sets.

• Physics First Electric Field Unit
• Conceptual Physics Electric Field Unit
• Algebra-Based Physics Electric Field Unit
• AP/Calculus-Based Physics Electric Field Unit