A-LEVEL Physics: 5.1.2: Current-Voltage Characteristics (SaveMyExams)

Question 1

Ohm’s Law:

Answer 1

For a Conductor at Constant Temperature, the Current Through it is Proportional to the Potential Difference Across it.

V=IR

Question 2

In Ohm’s Law, what does ‘Constant Temperature’ Imply?

Answer 2

Constant Temperature Implies Constant Resistance.

Question 3

Ohm’s Law is Represented by the Equation:

Answer 3

V=IR

Question 4

Ohm’s Law:

Answer 4

For a Conductor at Constant Temperature, the Current Flowing through it is Proportional to the Potential Difference Across it.

Question 5

In Ohm’s Law, what does ‘Constant Temperature’ Imply?

Answer 5

It Implies Constant Resistance.

Question 6

Ohm’s Law is Represented in the Equation:

Answer 6

V=IR

Question 7

By Adjusting the ___ on the Variable Resistor, the ___ & the ___ ___ Will Vary in the Circuit.

Answer 7

Resistance, Current, Potential Difference.

Question 8

Measuring the Variation of Current with Potential Difference Through a Fixed Resistor Will Produce a…

Answer 8

Straight Line Graph.

Question 9

What is an ‘Ohmic Conductor’?

Answer 9

An Ohmic Conductor is a Conductor that Obeys Ohm’s Law.

Question 10

What is a ‘Non-Ohmic Conductor?

Answer 10

A Non-Ohmic Conductor is a Conductor that does Not Obey Ohm’s Law.

Question 11

What will the I-V Graph of an Ohmic Conductor be?

Answer 11

Straight Line Through the Origin.

Question 12

What Type of Conductor is a Resistor?

Answer 12

Ohmic.

Question 13

What Type of Resistor is a Filament Lamp?

Answer 13

Non-Ohmic Conductor.

Question 14

As the Potential Difference (Voltage) Across a Component is Increased, the ___ Also Increases.

Answer 14

Current.

Question 15

In an Ohmic Conductor, Current & Voltage are ___ Proportional.

Answer 15

Directly.

Question 16

In an Ohmic Conductor, Current & Resistance are ___ Proportional.

Answer 16

Inversely.

Question 17

The Precise Relationship Between Current & Voltage is Different for Different Components, & Can be Shown on an…

Answer 17

I-V Graph.

Question 18

For an Ohmic Conductor, the I-V Graph is a…

Answer 18

Straight Line Through the Origin.

Question 19

For a Semiconductor Diode, the I-V Graph is a…

Answer 19

Horizontal Line that goes Sharply Upwards.

Question 20

For a Filament Lamp, the I-V Graph has…

Answer 20

An ‘S’ Shaped Curve.

Question 21

In an Ohmic Conductor, the Current is ___ Proportional to the Potential Difference. This is Shown by…

Answer 21

Directly. By a Straight-Line Through the Origin on the I-V Graph.

Question 22

There are 2 Directions that Current Can Flow Through a Diode: (2)

Answer 22

-Forward Bias.

-Reverse Bias.

Question 23

There are 2 Directions that Current Can Flow Through a Diode. What are they Shown by on an I-V Graph? (2)

Answer 23

-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.

Question 24

What does the I-V Graph for a Filament Lamp Show? Why is this?

Answer 24

It Shows the Current Increasing at a Proportionally Slower Rate than the Potential Difference.
This is Because it is a Non-Ohmic Conductor.

Question 25

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)

Answer 25

-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.

Question 26

Why is a Filament Lamp a Non-Ohmic Conductor? (3)

Answer 26

-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.

Question 27

For an I-V Graph where the Graph is a Straight Line, the Resistance is…

Answer 27

Constant.

Question 28

What does the Gradient of an I-V Graph Represent?

Answer 28

Resistance.

Question 29

When does the Filament Lamp Obey Ohm’s Law?

Answer 29

At Small Voltages.