T10 - electric circuits

Question 1

Kirchoff’s first law

Answer 1

total current into a junction = total current out

Question 2

Kirchoff’s second law

Answer 2

sum of emfs = sum of potential differences around a closed loop

Question 2

internal resistance

Answer 2

resistance of a source of emf due to its construction, which causes a loss in energy as the charge passes through the source

Question 3

terminal pd

Answer 3

the potential difference across an electrical power source - when there is no current this is equal to the emf of the source, if there is current in the source this is equal to emf minus lost volts

Question 4

lost volts

Answer 4

potential difference across the internal resistor of a source of emf

Question 5

potential divider

Answer 5

an electrical circuit designed to divide the pd across 2+ components in order to produce a specific output

Question 6

potentiometer

Answer 6

an electrical component with three terminals and some form of sliding contact that can be adjusted to vary the pd between two of the terminals