10.3 Analysing Circuits Flashcards
What is the effect on the total emf and total current in a circuit if an extra cell is added in series and in the same direction as the first cell
The emf would be greater therefore the total current would be greater
What is the effect on the total emf and total current in a circuit if an extra cell is added in series and in the opposite direction as the first cell
The total emf would be lower therefore a lower total current
What is the effect on the total emf and total current in a circuit if an extra cell is added in parallel with first cell
The total amount of energy supplied to the circuit increases however neither the total emf or current change
How can a flat cell be recharged
By connecting it in series in the opposite direction to a cell that still has charge
If you connect a voltmeter across the terminals of a power supply what s measured
Terminal p.d
Why does the gradient of the i-v graph for a filament lamp decrease as V increases
As more current flows through the filament the temperature increases
The atoms and ions within the wire vibrate more therefore colliding more often with the electrons flowing through it = higher resistance
So the gradient of the graph decreases
Describe the i-v characteristics for a diode
In the backwards direction = current is zero
In the forward direction = current is zero
Until the threshold voltage is reached then the current will flow
Define 1kWh
The energy used by a 1kW appliance in 1 hour
How is p.d distributed around a parallel circuit
The components in parallel have the same p.d
How is terminal p.d calculated when no current flows
The terminal p.d is equal to the e.m.f of the source
What is terminal p.d
The potential difference across an electrical power source
