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==Key Stage 2==
===Meaning===
An '''electrical bulb''' is a [[circuit ]] [[Electrical Component|component ]] that gives out [[light]] when [[electricity]] goes through it.
: Singular [[Noun]]: '''Electrical Bulb'''
===About Electrical Bulbs===
: There are many different kinds of '''electrical bulb'''.
: The type of '''electrical bulb''' you will use in class is called a [[Filament Bulb]]. It has a thin piece of wire inside that glows when electricity passes through it.
: '''Electrical bulbs''' can get very hot so you shouldn't touch the [[glass]].
{| class="wikitable"
|-
|[[File:FilamentBulb.png|center|100px]]
|[[File:BulbSymbol.png|center|200px]]
|-
| style="height:20px; width:200px; text-align:center;" |An '''electrical bulb'''.
| style="height:20px; width:200px; text-align:center;" |The symbol for an '''electrical bulb'''.
|}
==Key Stage 3==
===Meaning===
An '''electrical bulb''' is a [[circuit]] [[Electrical Component|component]] that gives out [[light]] when [[electricity]] goes through it.
===About Electrical Bulbs===
: There are many different kinds of '''electrical bulb'''.
: The type of '''electrical bulb''' used in class is called a [[Filament Bulb]]. It has a thin piece of wire called a filament that becomes so hot when [[electricity]] passes through it that it begins to glow.
: '''Electrical bulbs''' can get very hot so you shouldn't touch the [[glass]].
{| class="wikitable"
|-
|[[File:FilamentBulb.png|center|100px]]
|[[File:BulbSymbol.png|center|200px]]
|-
| style="height:20px; width:200px; text-align:center;" |An '''electrical bulb'''.
| style="height:20px; width:200px; text-align:center;" |The symbol for an '''electrical bulb'''.
|}
==Key Stage 4==
===Meaning===
[[File:BulbSymbol.png|right|300px|thumb|The symbol for an '''bulb'''.]]
An '''electrical bulb''' is a [[circuit]] [[Electrical Component|component]] that gives out [[light]] when [[electricity]] goes through it.
===About Electrical Bulbs===
: An '''electrical bulb''' usually refers to a [[Filament Bulb]]. However, there are other types.
: In a [[Filament Bulb|filament]] '''bulb''' [[Electrical Work|electrical work]] is done to [[heat]] the filament to a high enough [[temperature]] that it glows in [[Visible Light|visible light]], see [[Black Body Radiation|black body radiation]].
: The [[Electrical Current|electrical current]] has a [[heating]] effect on the filament which increases its [[temperature]]. This causes the [[Electrical Resistance|resistance]] to increase, so the '''bulb''' does not behave as an [[Ohmic Conductor|ohmic conductor]].
===IV Graph===
{| class="wikitable"
|-
|[[File:IVGraphBulb.png|center|400px]]
|}
====Description====
The [[IV Graph]] for a '''bulb''' shows that:
*As [[Potential Difference|potential difference]] increases, [[Electrical Current|current]] increases.
*At small [[Potential Difference|potential differences]]] the the relationship between [[Potential Difference|potential difference]] and [[Electrical Current|current]] is [[linear]] (the [[gradient]] is constant).
*At large [[Potential Difference|potential differences]] the [[gradient]] becomes more shallow as the [[Electrical Resistance|resistance]] of the '''bulb''' increases.
====Explanation====
* At small [[Potential Difference|potential differences]] there is a small [[Electrical Current|current]] so the [[heating]] effect of the [[Electrical Current|current]] is small and the [[filament]] remains at a low [[temperature]].
* At large [[Potential Difference|potential differences]] there is a large [[Electrical Current|electrical current]] so the [[heating]] effect of the [[Electrical Current|current]] is large which causes the [[filament]] to be a high [[temperature]].
** This is caused by [[electron]]s in the [[wire]] [[collide|colliding]] with [[ion]]s in the [[metal]] [[lattice]] causing them to [[vibrate]].
* [[Wire]]s (like the [[filament]]) have a greater [[Electrical Resistance|resistance]] at higher [[temperature]]s, causing the increase in [[Electrical Current|current]] to be reduced.
** This is because the more the [[ion]]s in the [[metal]] [[lattice]] [[vibrate]] the more likely [[electron]]s are to [[collide]] with them and slow down.
====Obtaining the IV Graph====
{| class="wikitable"
|-
|[[File:BulbIVGraphCircuit.png|center|300px]]
| style="height:20px; width:300px; text-align:left;" |
#Connect an [[ammeter]] in [[Series Circuit|series]] with the '''bulb''' to measure [[Electrical Current|current]] through the '''bulb'''.
#Connect a [[voltmeter]] in [[Parallel Circuit|parallel]] with the '''bulb''' to measure the [[Potential Difference|potential difference]] across it.
#Use a [[Variable Resistor|variable resistor]] in [[Series Circuit|series]] with the '''bulb''' to vary the [[Potential Difference|potential difference]] across the '''bulb'''.
#Start with a [[Potential Difference|potential difference]] of zero and increase the [[Potential Difference|potential difference]] by an interval of 1V up to 10V.
#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]].
|}
==Beyond the Curriculum==
{{#ev:youtube|https://www.youtube.com/watch?v=oCEKMEeZXug}}