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A [[Electrical Component|component]] in an [[circuit|electrical circuit]] which makes it difficult to [[electricity]] to pass through it.
+
==Key Stage 3==
 +
===Meaning===
 +
[[File:Resistor.png|right|300px|thumb|A picture of a [[resistor]].]]
 +
A [[resistor]] is a [[Electrical Component|component]] in an [[circuit|electrical circuit]] which makes it difficult to [[electricity]] to pass through it.
 +
 
 +
===About Resistors===
 +
: A [[resistor]] is a [[Electrical Component|component]] designed to have a particular [[Electrical Resistance|resistance]].
 +
: [[Resistor]]s are added to [[circuit]]s to control the [[Electrical Current|current]] which will pass through for a certain [[Potential Difference|potential difference]].
 +
: The greater the [[Electrical Resistance|resistance]] of a [[resistor]] the smaller the [[Electrical Current|current]] will be.
 +
: The [[Electrical Resistance|resistance]] of a [[resistor]] can be found by attaching an [[ammeter]] in [[Series Circuit|series]] with the [[resistor]] and a [[voltmeter]] in [[Parallel Circuit|parallel]] with the [[resistor]].
 +
: All [[electrical Component|component]]s in a [[circuit]] act as [[resistor]]s, including [[wire]]s. The longer a [[wire]] the more [[Electrical Resistance|resistance]] it will have to a [[Electrical Current|current]].
 +
 
 +
{| class="wikitable"
 +
|-
 +
|[[File:Resistor.png|center|200px]]
 +
|[[File:ResistorSymbol.png|center|200px]]
 +
|-
 +
| style="height:20px; width:200px; text-align:center;" |A [[resistor]].
 +
| style="height:20px; width:200px; text-align:center;" |The symbol for a [[resistor]].
 +
|}
 +
 
 +
==Key Stage 4==
 +
===Meaning===
 +
[[File:ResistorSymbol.png|right|300px|thumb|The symbol for a [[resistor]].]]
 +
A [[resistor]] is a [[Electrical Component|component]] in an [[circuit|electrical circuit]] which makes it difficult to [[electricity]] to pass through it.
 +
 
 +
===About Resistors===
 +
: A [[resistor]] is a [[Electrical Component|component]] designed to have a particular [[Electrical Resistance|resistance]].
 +
: [[Resistor]]s are added to [[circuit]]s to control the [[Electrical Current|current]] which will pass through for a certain [[Potential Difference|potential difference]].
 +
: The greater the [[Electrical Resistance|resistance]] of a [[resistor]] the smaller the [[Electrical Current|current]] will be.
 +
: The [[Electrical Resistance|resistance]] of a [[resistor]] can be found by attaching an [[ammeter]] in [[Series Circuit|series]] with the [[resistor]] and a [[voltmeter]] in [[Parallel Circuit|parallel]] with the [[resistor]].
 +
: All [[electrical Component|component]]s in a [[circuit]] act as [[resistor]]s, including [[wire]]s. The longer a [[wire]] the more [[Electrical Resistance|resistance]] it will have to a [[Electrical Current|current]].
 +
 
 +
===Resistors in Series===
 +
: Adding [[resistor]]s in [[Series Circuit|series]] increases the [[Electrical Resistance|resistance]] in the [[circuit]].
 +
: The [[Electrical Resistance|resistance]] of each [[resistor]] can be added together.
 +
{| class="wikitable"
 +
|-
 +
|[[File:ResistorsSeries1.png|center|400px]]
 +
| style="height:20px; width:175px; text-align:center;" |The [[Electrical Resistance|resistance]] between points A and B is:
 +
 
 +
5Ω.
 +
|-
 +
|[[File:ResistorsSeries2.png|center|400px]]
 +
| style="height:20px; width:175px; text-align:center;" |The [[Electrical Resistance|resistance]] between points A and B is:
 +
 
 +
2Ω + 5Ω = 7Ω
 +
|-
 +
|[[File:ResistorsSeries3.png|center|400px]]
 +
| style="height:20px; width:175px; text-align:center;" |The [[Electrical Resistance|resistance]] between points A and B is:
 +
 
 +
2Ω + 5Ω + 9Ω = 16Ω
 +
|}
 +
 
 +
===Resistors in Parallel===
 +
''NB: You only need to know what happens with identical [[resistor]]s in [[Parallel Circuit|parallel]].''
 +
 
 +
: When identical [[resistor]]s are added in [[Parallel Circuit|parallel]] there are more paths for the [[electricity]] so the [[Electrical Resistance|resistance]] is reduced.
 +
 
 +
{| class="wikitable"
 +
|-
 +
|[[File:ResistorsParallel2.png|center|200px]]
 +
|[[File:ResistorsParallel3.png|center|200px]]
 +
|[[File:ResistorsParallel4.png|center|200px]]
 +
 
 +
|-
 +
| style="height:20px; width:200px; text-align:center;" |Two identical [[resistor]]s in [[Parallel Circuit|parallel]] gives twice the number of paths, so has half the [[Electrical Resistance|resistance]].
 +
 
 +
The [[Electrical Resistance|resistance]] between points A and B is 12Ω.
 +
| style="height:20px; width:200px; text-align:center;" |Three identical [[resistor]]s in [[Parallel Circuit|parallel]] gives three times the number of paths, so has a third of the [[Electrical Resistance|resistance]].
 +
 
 +
The [[Electrical Resistance|resistance]] between points A and B is 8Ω.
 +
| style="height:20px; width:200px; text-align:center;" |Four identical [[resistor]]s in [[Parallel Circuit|parallel]] gives four times the number of paths, so has a quarter of the [[Electrical Resistance|resistance]].
 +
 
 +
The [[Electrical Resistance|resistance]] between points A and B is 6Ω.
 +
|}
 +
 
 +
===IV Graph===
 +
{| class="wikitable"
 +
|-
 +
|[[File:IVGraphResistor.png|center|400px]]
 +
|}
 +
====Description====
 +
The [[IV Graph]] for a [[resistor]] shows that:
 +
*As [[Potential Difference|potential difference]] increases, [[Electrical Current|increases]].
 +
*The relationship between [[Potential Difference|potential difference]] and [[Electrical Current|current]] is [[linear]] (the [[gradient]] is constant).
 +
*The [[Electrical Current|current]] is [[Directly Proportional|directly proportional]] to [[Potential Difference|potential difference]].
 +
 
 +
====Explanation====
 +
: [[Resistor]]s obey [[Ohm's Law]] so the "[[Electrical Current|current]] through a [[Electrical Resistor|resistor]] at constant [[temperature]] is [[Directly Proportional|directly proportional]] to the [[Potential Difference|potential difference]] across the [[resistor]]."
 +
 
 +
====Obtaining the IV Graph====
 +
{| class="wikitable"
 +
|-
 +
|[[File:ResistorIVGraphCircuit.png|center|300px]]
 +
| style="height:20px; width:300px; text-align:left;" |
 +
#Connect an [[ammeter]] in [[Series Circuit|series]] with the [[resistor]] to measure [[Electrical Current|current]] through the [[resistor]].
 +
#Connect a [[voltmeter]] in [[Parallel Circuit|parallel]] with the [[resistor]] to measure the [[Potential Difference|potential difference]] across it.
 +
#Use a [[Variable Resistor|variable resistor]] in [[Series Circuit|series]] with the [[resistor]] to vary the [[Potential Difference|potential difference]] across the [[resistor]].
 +
#Start with a [[Potential Difference|potential difference]] of zero and increase the [[Potential Difference|potential difference]] by an interval of 0.2V up to 2V.
 +
#Recording the reading on the [[voltmeter]] and [[ammeter]].
 +
#Reverse the connections on the [[battery]] and repeat steps 4 and 5 to find the I-V relationship for negative [[Potential Difference|potential difference]] and [[Electrical Current|current]].
 +
|}
 +
 
 +
===References===
 +
====AQA====
 +
 
 +
:[https://www.amazon.co.uk/gp/product/0008158770/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158770&linkCode=as2&tag=nrjc-21&linkId=ec31595e720e1529e49876c3866fff6e ''Resistor, pages 46-7, 52, GCSE Physics; Student Book, Collins, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/0008158770/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158770&linkCode=as2&tag=nrjc-21&linkId=ec31595e720e1529e49876c3866fff6e ''Resistor; non-ohmic, page 59, GCSE Physics; Student Book, Collins, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/0008158770/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158770&linkCode=as2&tag=nrjc-21&linkId=ec31595e720e1529e49876c3866fff6e ''Resistors in parallel, pages 55, 63, GCSE Physics; Student Book, Collins, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/0008158770/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158770&linkCode=as2&tag=nrjc-21&linkId=ec31595e720e1529e49876c3866fff6e ''Resistors in series, pages 54, 57, 63, GCSE Physics; Student Book, Collins, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1471851354/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851354&linkCode=as2&tag=nrjc-21&linkId=9012a0d354024419214fb3ad5ac44ba0 ''Resistors, pages 293, 295-6, GCSE Combined Science Trilogy 1, Hodder, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Resistors, pages 40-1, GCSE Physics, Hodder, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/019835939X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=019835939X&linkCode=as2&tag=nrjc-21&linkId=57e96876985fc39b1a3d8a3e3dc238b6 ''Resistors, pages 52-53, 55, 58-59, 61, 70, GCSE Physics; Third Edition, Oxford University Press, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Resistors, pages 60, 66, 77-79, GCSE Combined Science Trilogy; Physics, CGP, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Resistors, pages 62, 68, 79-81, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Resistors; circuit symbol, page 38, GCSE Physics, Hodder, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Resistors; I-V characteristics, pages 65, 66, GCSE Combined Science Trilogy; Physics, CGP, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Resistors; I-V characteristics, pages 67, 68, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Resistors; light-dependant resistors (LDRs), pages 60, 80, 81, GCSE Combined Science Trilogy; Physics, CGP, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Resistors; light-dependant resistors (LDRs), pages 62, 82, 83, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1471851354/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851354&linkCode=as2&tag=nrjc-21&linkId=9012a0d354024419214fb3ad5ac44ba0 ''Resistors; light-dependent (LDRs), pages 299-300, GCSE Combined Science Trilogy 1, Hodder, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1471851354/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851354&linkCode=as2&tag=nrjc-21&linkId=9012a0d354024419214fb3ad5ac44ba0 ''Resistors; ohmic and non-ohmic, page 298, GCSE Combined Science Trilogy 1, Hodder, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Resistors; ohmic and non-ohmic, page 43, GCSE Physics, Hodder, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1471851354/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851354&linkCode=as2&tag=nrjc-21&linkId=9012a0d354024419214fb3ad5ac44ba0 ''Resistors; thermistors, pages 298-9, GCSE Combined Science Trilogy 1, Hodder, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Resistors; thermistors, pages 60, 80, 81, GCSE Combined Science Trilogy; Physics, CGP, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Resistors; thermistors, pages 62, 82, 83, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Resistors; variable resistors, pages 60, 65, GCSE Combined Science Trilogy; Physics, CGP, AQA '']
 +
:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Resistors; variable resistors, pages 62, 67, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']
 +
 
 +
====Edexcel====
 +
 
 +
:[https://www.amazon.co.uk/gp/product/1782948163/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948163&linkCode=as2&tag=nrjc-21&linkId=0fdbfd5dd397d6e24a9dfb250f08587f ''Resistors (fixed), page 228, GCSE Physics, CGP, Edexcel '']
 +
:[https://www.amazon.co.uk/gp/product/1292120223/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120223&linkCode=as2&tag=nrjc-21&linkId=068ecf40278c32406a7f1c6e66751417 ''Resistors; parallel circuits, page 147, GCSE Physics, Pearson Edexcel '']
 +
:[https://www.amazon.co.uk/gp/product/1292120223/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120223&linkCode=as2&tag=nrjc-21&linkId=068ecf40278c32406a7f1c6e66751417 ''Resistors; series circuits, pages 146-147, GCSE Physics, Pearson Edexcel '']
 +
 
 +
====OCR====
 +
:[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Resistors, pages 104, 106, 110, 113, Gateway GCSE Physics, Oxford, OCR '']
 +
:[https://www.amazon.co.uk/gp/product/1782945695/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945695&linkCode=as2&tag=nrjc-21&linkId=ceafcc80bcad6b6754ee97a0c7ceea53 ''Resistors, pages 176, 178, 179, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR '']
 +
:[https://www.amazon.co.uk/gp/product/1782945687/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945687&linkCode=as2&tag=nrjc-21&linkId=9a598e52189317a20311d7a632747bc9 ''Resistors, pages 45-47, Gateway GCSE Physics; The Revision Guide, CGP, OCR '']

Latest revision as of 18:16, 18 December 2019

Contents

Key Stage 3

Meaning

 
A picture of a resistor.

A resistor is a component in an electrical circuit which makes it difficult to electricity to pass through it.

About Resistors

A resistor is a component designed to have a particular resistance.
Resistors are added to circuits to control the current which will pass through for a certain potential difference.
The greater the resistance of a resistor the smaller the current will be.
The resistance of a resistor can be found by attaching an ammeter in series with the resistor and a voltmeter in parallel with the resistor.
All components in a circuit act as resistors, including wires. The longer a wire the more resistance it will have to a current.
 
 
A resistor. The symbol for a resistor.

Key Stage 4

Meaning

 
The symbol for a resistor.

A resistor is a component in an electrical circuit which makes it difficult to electricity to pass through it.

About Resistors

A resistor is a component designed to have a particular resistance.
Resistors are added to circuits to control the current which will pass through for a certain potential difference.
The greater the resistance of a resistor the smaller the current will be.
The resistance of a resistor can be found by attaching an ammeter in series with the resistor and a voltmeter in parallel with the resistor.
All components in a circuit act as resistors, including wires. The longer a wire the more resistance it will have to a current.

Resistors in Series

Adding resistors in series increases the resistance in the circuit.
The resistance of each resistor can be added together.
 
 The resistance between points A and B is:

5Ω.

 
 The resistance between points A and B is:

2Ω + 5Ω = 7Ω

 
 The resistance between points A and B is:

2Ω + 5Ω + 9Ω = 16Ω

Resistors in Parallel

NB: You only need to know what happens with identical resistors in parallel.

When identical resistors are added in parallel there are more paths for the electricity so the resistance is reduced.
 
 
 
Two identical resistors in parallel gives twice the number of paths, so has half the resistance.

The resistance between points A and B is 12Ω.

Three identical resistors in parallel gives three times the number of paths, so has a third of the resistance.

The resistance between points A and B is 8Ω.

Four identical resistors in parallel gives four times the number of paths, so has a quarter of the resistance.

The resistance between points A and B is 6Ω.

IV Graph

 

Description

The IV Graph for a resistor shows that:

Explanation

Resistors obey Ohm's Law so the "current through a resistor at constant temperature is directly proportional to the potential difference across the resistor."

Obtaining the IV Graph

 
  1. Connect an ammeter in series with the resistor to measure current through the resistor.
  2. Connect a voltmeter in parallel with the resistor to measure the potential difference across it.
  3. Use a variable resistor in series with the resistor to vary the potential difference across the resistor.
  4. Start with a potential difference of zero and increase the potential difference by an interval of 0.2V up to 2V.
  5. Recording the reading on the voltmeter and ammeter.
  6. Reverse the connections on the battery and repeat steps 4 and 5 to find the I-V relationship for negative potential difference and current.

References

AQA

Resistor, pages 46-7, 52, GCSE Physics; Student Book, Collins, AQA
Resistor; non-ohmic, page 59, GCSE Physics; Student Book, Collins, AQA
Resistors in parallel, pages 55, 63, GCSE Physics; Student Book, Collins, AQA
Resistors in series, pages 54, 57, 63, GCSE Physics; Student Book, Collins, AQA
Resistors, pages 293, 295-6, GCSE Combined Science Trilogy 1, Hodder, AQA
Resistors, pages 40-1, GCSE Physics, Hodder, AQA
Resistors, pages 52-53, 55, 58-59, 61, 70, GCSE Physics; Third Edition, Oxford University Press, AQA
Resistors, pages 60, 66, 77-79, GCSE Combined Science Trilogy; Physics, CGP, AQA
Resistors, pages 62, 68, 79-81, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
Resistors; circuit symbol, page 38, GCSE Physics, Hodder, AQA
Resistors; I-V characteristics, pages 65, 66, GCSE Combined Science Trilogy; Physics, CGP, AQA
Resistors; I-V characteristics, pages 67, 68, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
Resistors; light-dependant resistors (LDRs), pages 60, 80, 81, GCSE Combined Science Trilogy; Physics, CGP, AQA
Resistors; light-dependant resistors (LDRs), pages 62, 82, 83, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
Resistors; light-dependent (LDRs), pages 299-300, GCSE Combined Science Trilogy 1, Hodder, AQA
Resistors; ohmic and non-ohmic, page 298, GCSE Combined Science Trilogy 1, Hodder, AQA
Resistors; ohmic and non-ohmic, page 43, GCSE Physics, Hodder, AQA
Resistors; thermistors, pages 298-9, GCSE Combined Science Trilogy 1, Hodder, AQA
Resistors; thermistors, pages 60, 80, 81, GCSE Combined Science Trilogy; Physics, CGP, AQA
Resistors; thermistors, pages 62, 82, 83, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
Resistors; variable resistors, pages 60, 65, GCSE Combined Science Trilogy; Physics, CGP, AQA
Resistors; variable resistors, pages 62, 67, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA

Edexcel

Resistors (fixed), page 228, GCSE Physics, CGP, Edexcel
Resistors; parallel circuits, page 147, GCSE Physics, Pearson Edexcel
Resistors; series circuits, pages 146-147, GCSE Physics, Pearson Edexcel

OCR

Resistors, pages 104, 106, 110, 113, Gateway GCSE Physics, Oxford, OCR
Resistors, pages 176, 178, 179, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR
Resistors, pages 45-47, Gateway GCSE Physics; The Revision Guide, CGP, OCR
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