Module 1 - Electricity and Magnetism

Kirchhoff’s Current Law

the sum of current at a junction in an electrical circuit is zero, underlying principle is that charge is conserved

Kirchhoff’s Voltage Law

states that the total e.m.f. in an electrical circuit is equal to the sum of the p.d across all the components which make up the circuit, underlying principle is that energy is conserved

Potential Divider

a circuit consisting of two or more resistors connected in series across a voltage supply, used to change the value of the supply voltage to the required voltage

Potentiometer

a variable potential divider that uses a sliding contact to adjust the output voltage continuously

key difference between potential divider and potentiometer

potential divider divides an input voltage into smaller voltages whereas a potentiometer allows the output voltage to be varied by moving a sliding contact