Semiconductors & Magnetism Flashcards
Semiconductor
A material whose resistivity is between that of a good conductor and a good insulator
Intrinsic Conduction
The movement of charges through a pure conductor
Extrinsic conduction
The movement of charges through a doped conductor
Doping
The addition of atoms of another element to a pure semiconductor to improve its conductivity
n-type Semiconductor
A semiconductor in which electrons are the majority of charge carriers
p-type Semiconductor
A semiconductor in which holes are the majority of charge carriers
The Coulomb
the amount of charge that passes any point in a circuit when 1A flows for 1 second
A magnetic field
Any region of space where magnetic forces can be felt
Magnetic flux density
at a point in a magnetic field, is a vector whose magnitude is equal to the force that would be experienced by a conductor of length 1m carrying a current of 1A at right angles to the field of at that point and whose direction is the direction of the force on a north pole placed at that point.
Magnetic flux
The product of flux density by area
Tesla
The magnetic flux density is 1 tesla if a conductor of length 1m carrying a current of 1A experiences a force of 1N
Electromagnetic Induction
When a conductor cuts a magnetic flux an emf is induced
Faraday’s Law
The size of the induced emf is proportional to the rate of change of flux
Lenz’s Law
The direction of the induced emf is always such as to oppose the change producing it
Mutual Induction
If a changing magnetic field in one coil causes an induced emf to appear in a nearby coil
