P6 - Electric Circuits Flashcards
Describe a series circuit [1]
An unbranched loop where the same charge passes through all components
Describe a parallel circuit [1]
A circuit in which the charge is split between branches
Describe the current across a series circuit [1]
The current is the same across all points in a series circuit
Describe current across a parallel circuit [1]
The current is divided between the brances of a circuit
Describe potential difference across a series circuit [1]
Potential difference is split between components according to the ratio of their resistances
Describe potential difference across a parallel circuit [1]
Each branch has a potential difference equal to the potential difference of the supply
What is total resistance in a series circuit? [1]
The sum of resistances from each component (Rₜₒₜₐₗ = R₁ + R₂…)
What is the total resistance in a parallel circuit? [1]
The total resistance is lower than that of the branch with the lowest resistance (1/Rₜₒₜₐₗ = 1/R₁ + 1/R₂…)
Why is it advantageous to connect lamps in parallel? [1]
If one lamp blows, the rest will be unaffected and can still receive current
Describe what happens with a thermistor [2]
As temperature increases / resistance decreases
Describe what happens with an LDR [2]
As light intensity increases / resistance decreases
What is the equation that links power and potential difference? [1]
Power = current x voltage (P=IV)
What is the equation that links energy and potential difference? [1]
Energy transferred = current x voltage x time (E=Ivt)
How is damaged insulation a hazard? [1]
Sections of wire can be left exposed and contact can result in electric shocks or pose a fire hazard
How does overheating occur? [1]
High currents cause the wires to heat up, melting the insulation and potentially causing a fire
