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Created page with "==Key Stage 4== ===Meaning=== An '''alternating current''' is an electrical current which changes direction. ===About Alternating Currents=== : '''Alte..."
==Key Stage 4==
===Meaning===
An '''alternating current''' is an [[Electrical Current|electrical current]] which changes direction.
===About Alternating Currents===
: '''Alternating currents''' are caused by alternating [[Potential Difference|potential differences]].
: '''Alternating currents''' have a [[frequency]] at which they alternate.
: [[Mains Electricity|Mains electricity]] is an '''alternating current''' working at a [[frequency]] of 50Hz, so the [[Electrical Current|current]] changes direction 50 times every [[second]].
: '''Alternating currents''' cannot be used to charge a [[Electrical Cell|cell]] or [[battery]].
: '''Alternating currents''' cannot be used in [[electrolysis]].
: '''Alternating currents''' are used in [[transformer]]s.
===Examples===
{| class="wikitable"
|-
|[[File:OscilloscopeScreenAC1.png|center|400px]]
|-
| style="height:20px; width:600px; text-align:center;" |An [[oscilloscope]] trace of '''mains electricity''' shows its [[frequency]] is 50Hz as the time [[period]] is 0.02s per oscillation and the peak [[Potential Difference|potential difference]] is 320V, but the [[Mean Average|average]] over time is 230V.
|}
===Meaning===
An '''alternating current''' is an [[Electrical Current|electrical current]] which changes direction.
===About Alternating Currents===
: '''Alternating currents''' are caused by alternating [[Potential Difference|potential differences]].
: '''Alternating currents''' have a [[frequency]] at which they alternate.
: [[Mains Electricity|Mains electricity]] is an '''alternating current''' working at a [[frequency]] of 50Hz, so the [[Electrical Current|current]] changes direction 50 times every [[second]].
: '''Alternating currents''' cannot be used to charge a [[Electrical Cell|cell]] or [[battery]].
: '''Alternating currents''' cannot be used in [[electrolysis]].
: '''Alternating currents''' are used in [[transformer]]s.
===Examples===
{| class="wikitable"
|-
|[[File:OscilloscopeScreenAC1.png|center|400px]]
|-
| style="height:20px; width:600px; text-align:center;" |An [[oscilloscope]] trace of '''mains electricity''' shows its [[frequency]] is 50Hz as the time [[period]] is 0.02s per oscillation and the peak [[Potential Difference|potential difference]] is 320V, but the [[Mean Average|average]] over time is 230V.
|}