4.1 - Charge and Current Flashcards Preview

OCR Physics A Level > 4.1 - Charge and Current > Flashcards

Flashcards in 4.1 - Charge and Current Deck (7):

What is a Coulomb?

The quantity of charge that passes a fixed point in one second


What is Electric Current?

A flow of charge. Measured in amperes (Amps or A)


What is Conventional Current?

A model used to describe the movement of charge in a circuit from the positive terminal of a cell to the negative terminal


What is Electron Flow?

The fact that charge carriers (electrons) flow from the negative terminal to the positive terminal


What is Kirchoff's First Law?

The sum of currents entering any junction is always equal to the sum of the currents leaving the junction


What is each letter in I=nAve?

I = Current
n = the number of free electrons per unit volume
A = cross sectional area of the wire
e = the charge on the electron (1.602 x 10^-19C)
v = the mean drift velocity of the electrons


What is 1 Coulomb in electrons?

1 coulomb is the amount of charge on 6.25x10^18 electrons or 1 Amp second