10 electrical circuits Flashcards
What is Kirchhoff second law?
around a closed loop, the sum of the emfs = the sum of pds
How do you find total resistance in a series circuit?
add the resistances together
How to find total resistance in a parallel circuit?
1/Rt = 1/R1 + 1/R2 …
What is a potential divider?
A circuit that splits P.D using resistors
What is the ‘maximum power transferee theorem’?
resistance of supply circuit = resistance of load circuit
What will any power supply ‘loose’?
energy
Is terminal pd more or less then the emf?
less
What is the difference between terminal pd and the emf known as?
lost volts
What are lost volts in terms of internal resistance?
the pd across and internal resistance, ‘r’
What does more current mean in terms of lost volts?
more lost volts
What uses low internal resistance?
rechargeable batteries
What uses high internal resistance?
anything that needs to keep a low current
