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Difference between revisions of "Diode"

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====Explanation====
 
====Explanation====
 
: The [[Electrical Resistance|resistance]] of a [[diode]] is very low for [[Electrical Current|current]] in the forward direction and very high in the back direction.
 
: The [[Electrical Resistance|resistance]] of a [[diode]] is very low for [[Electrical Current|current]] in the forward direction and very high in the back direction.
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====Obtaining the IV Graph====
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{| class="wikitable"
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|-
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|[[File:DiodeIVGraphCircuit.png|center|300px]]
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| style="height:20px; width:300px; text-align:left;" |
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#Connect an [[ammeter]] in [[Series Circuit|series]] with the [[diode]] to measure [[Electrical Current|current]] through the [[diode]].
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#Connect a [[voltmeter]] in [[Parallel Circuit|parallel]] with the [[diode]] to measure the [[Potential Difference|potential difference]] across it.
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#Use a [[Variable Resistor|variable resistor]] in [[Series Circuit|series]] with the [[diode]] to vary the [[Potential Difference|potential difference]] across the [[diode]].
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#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.
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#Recording the reading on the [[voltmeter]] and [[ammeter]].
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#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]].
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|}

Revision as of 18:16, 28 February 2019

Key Stage 4

Meaning

The symbol for a diode.

A diode is an electrical component which only allows electricity through in one direction.

About Diodes

Diodes have a low resistance in one direction but a very high resistance in the reverse direction.
Diodes can be used to change an alternating current into a direct current.

IV Graph

IVGraphDiode.png

Description

The IV Graph for a diode shows that:

Explanation

The resistance of a diode is very low for current in the forward direction and very high in the back direction.

Obtaining the IV Graph

DiodeIVGraphCircuit.png
  1. Connect an ammeter in series with the diode to measure current through the diode.
  2. Connect a voltmeter in parallel with the diode to measure the potential difference across it.
  3. Use a variable resistor in series with the diode to vary the potential difference across the diode.
  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.