EF: Electric Field
Introductory Physics

Micro-model of Charge, Q-transfer, Conductors vs. Insulators

Electric Forces and Coulomb's Law (method 1)

Combined Coulomb’s (electric forces) and Newton’s second laws practice problem

Two ping pong balls filled with air are tied to a very light 0.5 meters-long string. The loose ends of the strings are taped to the same position on a horizontal ceiling. When both are equally rubbed with the same material, they develop a static charge and repel each other, making an angle of 30° with respect to the vertical. (m = 3 grams) 

Field Model, Charges in an Electric Field

Electric Field from Point Charges

Electric Fields Patterns

Electric flux, and Gauss's law (method 2)

Electric Flux and Gauss's Law - Explained

Notes and More Practice Problems 

Electric field and electric potential