Every atom is composed of Electrons, Protons, and Neutrons. These particles can interact with each other via electric forces, which are calculated via Coulombs Law. A positive particle will attract a negative particle and vice-versa. While most atoms are neutral (equal proton and electron count), atoms with more positive charge than a negative charge have a net-positive charge, and vice versa. Objects in the real-world that are composed of many atoms are either insulators (restrict movement of these atoms) or conductors (allow free movement). By knowing the basics of electricity, we can get into more advanced concepts used by physicists everywhere.
Electric charge (q) is a fundamental property of certain particles. The smallest amount of isolatable charge is the elementary charge (e), equal to 1.6×10-19 coulombs. Charge can be positive or negative.
Protons have a charge of +1e. Electrons have a charge of −1e. Neutrons are neutral. Atoms with an excess of protons or electrons are known as ions.
Charges can move freely in conductors. Charges cannot move freely in insulators.
Like charges repel, opposite charges attract. Coulomb’s Law describes the magnitude of the electrostatic force between charges.
Charging by contact is known as conduction. If a charged conductor is brought into contact with an identical neutral conductor, the net charge will be shared across the two conductors. Charging an object without placing it in contact with another charged object is known as induction.
When a charged object is brought near a conductor, the electrons in the conductor are free to move. When a charged object is brought near an insulator, the electrons are not free to move, but they may spend a little more time on one side of their orbit than another, creating a net separation of charge in a process known as polarization. The distance between the shifted positive and negative charges, multiplied by the charge, is known as the electric dipole moment.
Electric Charge & Coulomb's Law
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.
This book includes a comprehensive review of the key AP Physics C concepts and targeted strategies for acing every section of the exam. Additionally, the book includes two full length practice tests with full answer explanations.
The book offers a complete review of your AP course, strategies to give you the edge on test day, and plenty of practice with AP-style test questions. It includes 2 full length practice exams modeled on the real test, 3 separate plans to fit your study stle, review material updated to the most recent tests, and all the terms and concepts you need to know.