Resistance and I-V Characteristics - PRACTICAL Flashcards
Electricity (14 cards)
What does the term ‘I-V characteristic’ refer to?
A graph showing how the current flowing through a component changes as the potential difference across it is increased.
What type of I-V characteristic do linear components have?
A straight line (e.g. a fixed resistor).
What type of I-V characteristic do non-linear components have?
A curved line (e.g. a filament lamp or a diode).
What is the first step to find a component’s I-V characteristic?
Set up the test circuit.
What does varying the variable resistor do in the experiment?
Alters the current flowing through the circuit and the potential difference across the component.
What should you do after taking several pairs of readings from the ammeter and voltmeter?
Repeat each reading twice more to get an average for each current.
What is the purpose of swapping over the wires connected to the battery?
To reverse the direction of the current.
What should you plot after conducting the experiment?
A graph of current against voltage for the component.
What does the I-V characteristic for an ohmic conductor look like?
A straight line.
What happens to the temperature of the filament lamp as the current increases?
The temperature of the filament increases.
In what direction can current flow through a diode?
Current can only flow in one direction.
What relationship does current have to potential difference in a diode?
Current is directly proportional to potential difference until the graph gets shallower.
What is the behavior of a diode in the reverse direction?
It has a very high resistance.
How can resistance be calculated from the I-V characteristic?
By calculating R = V/I.
