### Kirchhoff's Rules

**Current Rule or Junction Rule**(conservation of charge)- The algebraic sum of the currents entering any junction must equal the sum of the currents leaving that junction.
- Therefore, in a series circuit the current is the same everywhere.
**Voltage Rule or Loop Rule**(conservation of energy)- The algebraic sum of the potential differences (voltage drops) around a closed conducting loop must equal zero.
- Therefore, components connected in parallel have the same voltage across them.

### Ohm's Law

where voltage ** V** is in volts, resistance

**is in ohms and current**

*R***is in amperes.**

*I*### Joule's Law

where power ** P** is in Watts, voltage

**is in volts, resistance**

*V***is in ohms and current**

*R***is in amperes.**

*I*### ThÃ©venin's Theorem

Any two-terminal network of resistors and voltage sources is equivalent to a single resistor in series with a single voltage source.

### Definitions

1 ampere = 1 coulomb/second

1 coulomb = 1 ampere · second

1 farad = 1 coulomb/volt

1 joule = 1 newton · meter

1 newton = 1 kg · meter/second^{2}

1 ohm = 1 volt/ampere

1 volt = 1 joule/coulomb

1 Watt = 1 joule/second

### Symbols, Dimensions and Units of Physical Quantities

Quantity | Common Symbol | Unit | Unit Symbol |
---|---|---|---|

Capacitance | C | farad | F |

Charge, electrical | q, Q, e | coulomb | C |

Current | I | ampere | A |

Energy | E, U | joule | J |

Force | F | newton | N |

Frequency | f, v | hertz | Hz |

Length | l, L | meter | m |

Potential, electrical or Voltage | V | volt | V |

Power | P | Watt | W |

Resistance | R | ohm | |

Time | t | second | s |

Work | W | joule | J |

## No comments:

Post a Comment