A-LEVEL Physics: 5.3.2: Series & Parallel Circuits (SaveMyExams) Flashcards
(19 cards)
in series circuit, current is ___ through all components
same
current in parallel circuits:
current splits at branches
total current in junction = total current out junction
what determines how current is split at branches in parallel circuit?
the total resistance of the components within each branch
the amount of current in each branch of a parallel circuit depends on…
total resistance of the components within that branch
how is the emf of power supply shared amongst the components in a series circuit?
each component gets a share of emf depending on their resistance
how is the emf of power supply shared amongst the components in a parallel circuit?
total voltage of each branch = emf
total voltage of combined cells can be calculated in the same way as voltage: (2)
-series: Vtotal = V1 + V2 …
-parallel: Vtotal = voltage of 1 cell
(series) Vtotal = …
= V1 + V2 + V3 …
(parallel) Vtotal = …
= V1 = V2 = V3 …
Kirchoff’s first law (law of conservation of charge):
sum of current entering junction = sum of current leaving junction
junction:
point where circuit paths meet
branch:
path connecting 2 junctions
if circuit is split into 2 branches, current before split should =…
current after the split
law of conservation of energy:
energy is never created nor destroyed, only transferred
Kirchoff’s second law:
total emf in a closed circuit = sum of potential difference across each component
what is Kirchoff’s second law a result of?
law of conservation of energy
(series) sum of voltages = …
total emf of power supply
in a parallel circuit, the voltage is the same across each…
closed loop
closed-circuit loops:
parallel circuits are made up of multiple closed-circuit loops.
each closed-circuit loop acts as its own, independent series circuit. separates at a junction.
