Ch 1 Flashcards
Force of attraction or repulsion of 2 charged particles.
Electrostatic Force
Measures how large the electrostatic force is between 2 charged objects.
Potential Difference
Sum of all potential differences around a circuit.
Electromotive Force
Charged bodies attract or repel each other with a force that is proportional to their charges and is inversely proportional to the square of the distance between them.
Coulombs Law
measured at any 2 points in an electrical circuit?
Potential Difference
Unit for potential difference and electromotive Force
Volt
What occurs when energy is gained by free electrons?
Voltage Rise
What occurs when energy is lost by free electrons?
Voltage Drop
Material with electrons loosely bound to its atoms or that permits free motion of a large number of electrons.
Conductor
Material with electrons tightly bound to its atoms and requires large amounts of energy to free electrons from its nuclei.
Insulator
Material that conducts electricity, but opposes current flow.
Resistor
Current flow from negative to positive potentials.
Electron Current Flow
Current that flows continuously in the same direction.
Direct Current
Current that periodically reverses direction.
Alternating Current
Alternately stores and releases electrical energy by the strength of the electrostatic field in the dielectric.
Capacitor
Measure of the size of the charge that can be stored in the capacitor.
Capacitance
Force that is the result of electrons spinning.
Magnetism
Small regions in a magnetic material where the force from electron spin does not cancel out.
Magnetic Domains
Group of magnetic field lines emitted outward from the North Pole of a magnet. Formed by alignment of domains with magnetic material.
Magnetic Flux
Materials that contain domains which can align to form a magnetic flux around the material.
ie steel, iron, nickel, cobalt
Magnetic Materials
Ability of a material to concentrate magnetic flux.
Permeability
States that like poles repel and unlike poles attract.
Law of Magnetism
What depends on the number of turns of a coil and how fast the conductor cuts across the magnetic lines of force or flux?
Magnitude of induced voltage
These are used to open/close electromagnetic devices.
ie such as relays, starters, valves
Magnetic Coils
Opposition to changes in current flow of a circuit.
Inductance
Process of generating a voltage in a conductor
By having the conductor cut across flux lines of a magnetic field.
Induction
Property of a coil to generate CEMF to oppose changes in current flow through itself.
Self-Induction
Area under the influence of electrostatic charges. Any electrons will be acted upon by electrostatic Force.
Electrostatic Field
Valence electrons that leave the atom. They gain energy and create an electrical pressure.
Free electrons
Units
Amp / Current / I
Volt / voltage / E
Ohm / Resistance / R
Watt / power / P
- Number of turns of a coil
- How fast conductor cuts across magnetic line of force.
- Strength of magnetic field
Faradays Law
Generated voltage that opposes voltage applied to the coil.
- Occurs when magnetic field is changing
- Magnitude of CEMF depends on strength of magnetic field and how fast field is changing.
Counter Electromotive Force CEMF
Force that holds electrons in orbit.
Electrostatic Force
