electric current

conventional current

direction in which positive charges flow

charge carrier

charged particle that contributes to an electric current like protons, electrons or ions

quantised

when a quantity has a definite minimum magnitude and only comes in multiples of the magnitude

current

rate of flow of electric charge past a place

charge formula

current * time

coulomb

the charge that flows past a point in a circuit in 1 second when the current is 1A

elementary charge

1.6X10^-19C

number density

number of charge carriers per unit volume in a material

mean drift velocity

average speed of a collection of charged particles when there is a current in a conductor

equation for current

I=nAvq…n is the number density…A is cross sectional area of the conductor…v is the mean drift velocity…q is the charge on each charge carrier

voltage formula

v=I/nAe

current increases

drift velocity increases

wire thinness

electrons move more quickly for a given current

material with lower electron density

mean drift velocity increases

number of electrons formula

n*A*l