Electric Parallel Circuits Calculations

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Electric Parallel Circuits Calculations
Bill Gates is the chairman, chief software
architect, and cofounder (with Paul Allen) of
Microsoft Corporation, The companys success made
Gates the worlds richest person.
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Ohms law

• R Resistance (control of the flow of electrons)
• I Current ( the amount of electron flow
  )
• V Volts ( the pressure of the charges
  )
• R V
• I

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Amperes in a Parallel Circuit

• The net change in amperes around the circuit is
  equal to zero
• It I1 I2 I3
• The Ampere divider is the resistor
• V I1R1 , V I2 R2, V I3 R3
• Note The voltage ( V ) is constant throughout
  the Parallel circuit

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Resistance in a Parallel Circuit

• Each resistor divides the Total resistance of the
  circuit (equivalent resistance)
• 1 1 1 1
• Reg R1 R2 R3
• The Ampere divider is the resistor
• V I1R1 , V I2 R2, V I3 R3
• Note The voltage ( V ) is constant throughout
  the Parallel circuit

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Sample problem

• A 2 ohm resistor , 3 ohm and 6 ohm resistor is
  connected in parallel to a 24 volt battery
• Draw circuit diagram
• Calculate the total resistance
• Calculate the total amperes

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Circuit diagram
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Calculations Resistance
1 1 1 1 Reg R1 R2 R3
1 1 1 1 Reg 2W 3W 6W
1 3 2 1 Reg 6W 6W 6W
1 6 Reg 6W
Reg 1W
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Calculation Amperes
V IR
24 V I(1W)
24 V I (1W)
24A I
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Summary

• In a Parallel Circuits the amperes add with each
  new device (resistance)
• Resistors control the voltage and current of
  power sources
• The reciprocal of the total resistance is equal
  to the sum of individual reciprocal resistance
• The Total voltage is constant throughout the
  circuit