I-V Characteristics Flashcards
(4 cards)
What is the I-V characteristic for a fixed resistor?
A straight line through the origin.
As it is directly proportional.
Obeys Ohms Law so is an ohmic conductor.
Resistance of resistor is constant.
Different resistors produce a straight line through the origin as well but with different gradients. The shallower the line the greater the resistance.
What is the I-V characteristic for a Filament Lamp?
Not a straight line through the origin.
More like an S shape.
So p.d. in filament lamp is not directly proportional to the current through the resistor.
Filament lamp is a non-ohmic component.
Does not obey Ohms Law.
Resistance of filament lamp is not constant.
What is the I-V characteristic for a diode?
At first, it remains level.
Once it reaches the threshold p.d. the resistance gradually starts to decrease. Graph goes up slowly.
Once p.d. gets much higher the diode has very little resistance. Graph goes up faster.
What is a diode?
A diode only allows a current in one particular direction.
A diode does not obey ohms law so it is a non-ohmic component.
Resistance of a diode is not constant.
