SPC REVISION Flashcards
(18 cards)
What is current?
current is the rate of flow of charge
equation for current
I=Q/T
What is potential difference?
IS THE WORK DONE PER UNIT CHARGE BETWEEN TWO POINTS IN A CIRCUIT
Equation of potential difference
V=W/Q
What is resistance?
resistance is a measure of how difficult it is for charge to pass through a component
Resistance equation
R=V/I
State ohms law
OHMS LAW STATES THAT FOR AN OHMIC CONDUCROR THE CURRENT IS DIRECTLY PROPORTIONAL TO THE POTENTIAL DIFFIRENCE ACROSS I, PROVIDED THE TEMPERATURE IS CONTANT.
LAW OF CONSERVATION OF CHARGE
the total electric charge in a closed system does not change.
State Kirchhoff’s first law
the total current in to a junction is equal to the current going out of the junction.
In a series circuit
the current is the same everywhere in the circuit
In a parallel circuit
the sum of the currents across each parallel set of branches is equal to the total current
LAW OF CONSERVATION OF ENERGY
States that energy cannot be created or destroyed but can be transferred form one form to the other
Kirchhoff’s second law
sum of voltages in series circuit is equal to the emf
KIRCHHOFFS SECOND LAW (PARALLEL)
THE P.D ACROSS EACH BRANCH IS EQUAL
Resistance in a series circuit
R=R1+R2+R3….
Resistance in parallel circuit
1/R=1/R1+1/R2+1/R3
WHAT IS POWER
the energy transferred over time
what is an electron volt
the amount of energy a single electron gains when it passes across a P.D of one volt
