Flashcards in C10 Terms Deck (58)
Stationary electrical charges and the forces that they exert
Is much stinger than gravity
Like charges repel unlike charges attract
law of charges
The net positive or negative charge is measured in?
The creation of a charged region on a neutral object when exposed to a nearby electrical charge is?
A neutral molecule whose electrons have shifted to from positive and negative ends or poles is?
Changes can be detected with what instrument?
Materials that offer little resistance to electron motion.
A loss of static charges.
A device used to protect buildings from lightning
The first capacitor
A devise that stores electrical charges
Electricity that involves continuously moving charges is called?
Most TVs contain a large vacuum tube screen called?
cathode-ray tube (CRT)
Electrons that have kinetic energy have?
electrical potential energy
The flow of positive charges through a conductor is called?
Current that flows in one direction is called?
The compleat path from the source of electrons to the end is called?
Something that electricity to some other useful form is called?
Allows you to open or close the circuit.
Consists of one or more electromechanical cells that supply electrons released by a chemical reaction.
Supplies electrons released by a chemical reaction.
We measure potential difference with a unit called?
The unit in which electrical current is measured.
The resistance to electrical flow is called?
What changes the voltage of the current in an electrical circuit?
Ohm's law state that.
As the size of the voltage changes the current is directly proportional the the voltage change, and the current is directly proportional to the resistance.
The unit that resistance is measured in.
The unit of electrical energy used by utilities to sell electricity.
What is the term for a circuit that has several loads on one wire?
What is it called when the current branches into parallel paths with the loads on each of the paths?
What is it called when the positive and negative wires touch and the current takes the easiest way to ground?
What device stops the current when it exceeds a set limit?
What is the device that detects short circuits?
What is a breaker that detects arcs in a circuit?
arc-fault circuit interrupter (AFCI)
A metal glass container that melts when the current overloads.
What device protects users from electrocution
ground-fault circuit interrupter (GFCI)
What causes electrical charges to attract and repel? How does the strength of this force compare to the gravitational force?
The electrostatic force. It is greater than gravity.
How many kinds of electrical charges are there? What are they called?
Two. Negative and positive.
What makes most every day objects electrically neutral?
They are neutrally charged.
What produces a negative charge on an object? A positive charge?
When there is more electrons than protons. When there is more protons than electrons.
As like charges move closer together, their lines of force bend farther away from each other and push together into a smaller space. What does this indicate about the size of the forces between them?
They are the same
How can you tell that an electroscope has an electrical charge?
The needle will move
Describe electrical conductors and insulators and give one example of each. What do we call materials that conduct electricity only under special circumstances
Conductors offer little resistance to electron motion a insulant does not. The copper in a wire is a conductor and the plastic coating on the outside is an insulant
What was the first devise to successfully store electrical charges?
The Leyden Jar
Name two devices that use static electricity to compleat a task.
An electrostatic precipitator, and a photocopier
(True or False) Lightning is a rapid electrostatic discharge.
Compare the two models of how electrons flow through a conductor
The first is the electron diffusion theory that states that electrons flow from areas of high concentration to areas of low concentration, and the second is the flow of electrons from a point of higher potential energy to a point of lower potential energy
What is the name for current that flows in one direction?
Direct current or DC
What are the minimum components needed for an electrical circuit to work? What device allows us to control whether or not current flows in a circuit?
The source and the load. A switch
What is the unit for electrical potential difference? How is it defined in terms of other SI units?
The volt. It is defined in the formula
What is the unit of electrical current?
The ampere (A)
What is the unit of electrical resistance?
What happens to the current in a short circuit? What can potentially result from a short circuit?
The current bypasses the load. A fire can be the result.
What common electrical safety device is designed to prevent electrical fires?
Give two reasons why circuit breakers are more effective and convenient than fuses.
They trip instantly not allowing a fire to start and they can be reused.
Why can a person be shocked to death by less current than is required to start a fire?
Because it does not take much current to stop the heart.