Chapter 22 - Electrostatics Flashcards
What are the rules of Electrical Forces?
Like charges repel & unlike charges attract.
What are Protons?
Protons have a positive net charge.
What are Electrons?
Electrons have a negative net charge.
How are Protons and Electrons related?
Protons/Electrons are equal in magnitude but opposite in sign (+/-).
Is the nucleus of an atom positive or negative? What surrounds the nucleus?
The nucleus is positive! Electrons (-) surround the nucleus.
What is the law of Conservation of Charge?
Electrons are never created nor destroyed, only transferred.
Are Protons or Electrons transferred? Or both?
Only electrons are transferred!
What is an Ion?
An ion is a charged atom.
What is Coulomb’s Law?
Coulomb’s Law states that electrical force DECREASES as the square of the distance between charged bodies INCREASES.
Ex.) F = 1/9 when distance is x3
(Think inverse-square law!)
What is the equation for Coulomb’s Law?
F =k(q1 x q2)/r^2
What value is “k” in Coulomb’s Law?
9.0 x 10^9 * Nm^2/C^2
What are Coulombs? (C)
Coulomb is the unit used for electrical charge.
What is a Conductor?
A conductor is a material that electric charge can flow through.
Are metals conductors or insulators?
Metals are conductors!
Are most plastics conductors or insulators?
Many plastics are good insulators!
What is a Semiconductor?
A semiconductor is a material that can be made to behave as either an insulator or a conductor at a given time.
When do semiconductors act as conductors?
When light of the proper color shines on it.
What is a Transistor?
Transistors use electrical signals to control others.
What is a Superconductor?
A superconductor is a material that has ZERO resistance to the flow of charge.
What is Charging by Contact?
Charging by contact is when electrons are transferred through simple touching/rubbing.
What is Charging by Induction?
Charging by induction is when electrons are transferred by the influence of a charged object near by. (NOT physically touching).
What is transferred through friction?
Electrons! This is a physical form of charging.
What does it mean when something is Electrically Polarized?
When something is electrically polarized, one side is slightly more positive or negative than the other. The sides are uneven.
What is an Electric Field?
An electric field is an energetic area that extends through space (just like gravitational fields!)
What is the equation for an Electric Field?
E = F/q
What material can completed shield an electric field?
Metals!
What is Electric Potential Energy?
Electric potential energy is the energy a charge has because of its location in an electric field.
What is interchangeable with Electric Potential?
Volts (Voltage).
How do you find Voltage?
Electric Potential Energy (J)/Charge (C)
A high voltage will have a ____ net charge.
A SMALL net charge!
What is a Capacitor?
A capacitor is a device used to store charge/electric energy.
What is the net charge of a Charged Capacitor?
A charged capacitor has a net charge of 0.
