A-LEVEL Physics: 5.1.2: Current-Voltage Characteristics (SaveMyExams) Flashcards
Ohm’s Law:
For a Conductor at Constant Temperature, the Current Through it is Proportional to the Potential Difference Across it.
V=IR
In Ohm’s Law, what does ‘Constant Temperature’ Imply?
Constant Temperature Implies Constant Resistance.
Ohm’s Law is Represented by the Equation:
V=IR
Ohm’s Law:
For a Conductor at Constant Temperature, the Current Flowing through it is Proportional to the Potential Difference Across it.
In Ohm’s Law, what does ‘Constant Temperature’ Imply?
It Implies Constant Resistance.
Ohm’s Law is Represented in the Equation:
V=IR
By Adjusting the ___ on the Variable Resistor, the ___ & the ___ ___ Will Vary in the Circuit.
Resistance, Current, Potential Difference.
Measuring the Variation of Current with Potential Difference Through a Fixed Resistor Will Produce a…
Straight Line Graph.
What is an ‘Ohmic Conductor’?
An Ohmic Conductor is a Conductor that Obeys Ohm’s Law.
What is a ‘Non-Ohmic Conductor?
A Non-Ohmic Conductor is a Conductor that does Not Obey Ohm’s Law.
What will the I-V Graph of an Ohmic Conductor be?
Straight Line Through the Origin.
What Type of Conductor is a Resistor?
Ohmic.
What Type of Resistor is a Filament Lamp?
Non-Ohmic Conductor.
As the Potential Difference (Voltage) Across a Component is Increased, the ___ Also Increases.
Current.
In an Ohmic Conductor, Current & Voltage are ___ Proportional.
Directly.
In an Ohmic Conductor, Current & Resistance are ___ Proportional.
Inversely.
The Precise Relationship Between Current & Voltage is Different for Different Components, & Can be Shown on an…
I-V Graph.
For an Ohmic Conductor, the I-V Graph is a…
Straight Line Through the Origin.
For a Semiconductor Diode, the I-V Graph is a…
Horizontal Line that goes Sharply Upwards.
For a Filament Lamp, the I-V Graph has…
An ‘S’ Shaped Curve.
In an Ohmic Conductor, the Current is ___ Proportional to the Potential Difference. This is Shown by…
Directly. By a Straight-Line Through the Origin on the I-V Graph.
There are 2 Directions that Current Can Flow Through a Diode: (2)
-Forward Bias.
-Reverse Bias.
There are 2 Directions that Current Can Flow Through a Diode. What are they Shown by on an I-V Graph? (2)
-Forward Bias: Shown by Sharp Increase in I & V on the Right Side of the Graph.
-Reverse Bias: Shown by a Zero Reading of Current or Pd on the Left Side of the Graph.
What does the I-V Graph for a Filament Lamp Show? Why is this?
It Shows the Current Increasing at a Proportionally Slower Rate than the Potential Difference.
This is Because it is a Non-Ohmic Conductor.
The I-V Graph for a Filament Lamp Shows the Current Increasing at a Proportionally Slower Rate than the Potential Difference. Why is this? (3)
-As the Current Increases, the Temperature of the Filament in the Lamp Increases, as More Electrons are Flowing Through it.
-Since the Filament is a Metal, the Higher Temperature Causes an Increase in Resistance.
-Resistance Opposes the Current, Causing the Current to Increase at a Slower Rate than the PD.
Why is a Filament Lamp a Non-Ohmic Conductor? (3)
-As the Current Increases, the Temperature of the Filament in the Lamp Increases, as More Electrons are Flowing Through it.
-Since the Filament is a Metal, the Higher Temperature Causes an Increase in Resistance.
-Resistance Opposes the Current, Causing the Current to Increase at a Slower Rate than the PD.
For an I-V Graph where the Graph is a Straight Line, the Resistance is…
Constant.
What does the Gradient of an I-V Graph Represent?
Resistance.
When does the Filament Lamp Obey Ohm’s Law?
At Small Voltages.
