# Formulas to Memorize:

- -Circle Area = π
*r*^{2} ^{-Series -Amps = Same}^{-Parallel – Volts = Same}^{ – 1/Rt = 1/R1 + 1/R2 + etc.}^{-RPM = 120xHz/Poles}^{-1}ø^{VD = 2KIL/CM}^{-3}ø^{VD}= /3KIL/CM^{-Short-Circuit Amps (SCA) = Amp / %Z/100}

^{ALSO:}

^{HP = KW/746}

# Formula Wheel

Used for circuits of VDC or VAC with Unity Power Factor

4 Quadrants divided into 12 Total

## Formula Wheel Memorization Tool

Formula Wheel Memorization Tool | |
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* = 2 | EAR PIE |

√ = 2 | PRPR Ib4E w/’s |

÷ = 4 | Eiri Peep Irie |

x² = 4 | PRPR Vertical-Inverted RP’s |

See Formula Wheel Memorization Tool below |

Remember this column: | Use 1st Column as a reminder to remember this column: | Now remember the Details: | ||||
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* = 2 |
EAR PIE | E=I*R & P=I*E |
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√ = 2 |
PR PR | I = √ P / R |
I before E I has slants (I, √, /) |
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E = √ PR |
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÷ = 4 |
Eiri Peep Irie | E |
= |
P |
÷ |
I |

I |
= |
E |
÷ |
R |
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R |
= |
E |
÷ |
I |
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I |
= |
P |
÷ |
E |
||

x² = 4 | PRPR | P |
= |
R |
* |
I² |

R |
= |
P |
÷ |
I² |
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P |
= |
E² |
÷ |
R |
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R |
= |
E² |
÷ |
P |
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**I = E / R**- Used to find current flowing through each resistor
- E is VD across each resistor, not voltage source

- Determines current of each parallel branch

- Used to find current flowing through each resistor
**I=E**_{s}/R_{t}- E
_{s}= power supply voltage - R
_{t}= Total circuit resistance

- E
**P = I**^{2}R- Power as a result of current flowing through a resistance
- Power can be calculated through P = I
^{2}R*or*Resistance Law of Proportion

# Ohms Law Formula Circle

- Ohms Law is opposition to current flow
- Relationship between a circuits current intensity (I), electro-motive force (E), and resistance (R)
- Current flow equals Voltage divided by Resistance
- Current is inversely proportional to Resistance
- When Resistance decreases, with Voltage constant, Current increases & vice versa

- I is directly proportional to E, & inversely proportional to R

# PIE Formula Circle

- Demonstrates relationship between power, current, and voltage