Accuracy number of significant decimal digits

Metric System

Joule [J]
Kilojoule [kJ]
Kilogram-meter [KGm]
Watt hour [Wh]
Kilowatt hour [kWh]
Erg [erg]

Calories

Calorie [cal] ^{*}
Kilocalorie [kcal]

Imperial System

foot-poundal [ft pdl]
inch-pound force [in lbf]
foot-pound force [ft lbf]
horsepower-hour [hph]
BTU^{**}

Atomic

Electronvolt [eV]
Hartree [E_{h}]
Rydberg [Ry]

Joule - Energy Unit

Unit of energy in the International System Of Units (SI) is Joule.
Joule is the derived unit. Joule formula:
1 J = 1 N · m = 1 kg · m^{2} / s^{2}

One joule is the amount of energy required to perform the following actions (source:wikipedia.org)**Joule to calorie formula**: Based on International Steam Table (1956)
1 calorie is defined to be exactly 4.1868J. Ergo:

1 cal = 4.1868J => N calories = N*4.1868 J

1 J = 0.238846 cal => N joules = N*0.238846 calories.

One joule is the amount of energy required to perform the following actions (source:wikipedia.org)

- The work done by a force of one newton traveling through a distance of one meter;
- The work required to move an electric charge of one coulomb through an electrical potential difference of one volt; or one coulomb volt, with the symbol C·V;
- The work done to produce power of one watt continuously for one second; or one watt second (compare kilowatt hour), with the symbol W·s. Thus a kilowatt hour is 3,600,000 joules or 3.6 megajoules;
- The kinetic energy of a 2 kg mass moving at a velocity of 1 m/s.

1 cal = 4.1868J => N calories = N*4.1868 J

1 J = 0.238846 cal => N joules = N*0.238846 calories.

Unit | In Joules |
---|---|

Metric System | |

Joule [J] | 1 |

Kilojoule [kJ] | 1000 |

Kilogram meter [KGm] | 9.80665 |

Watt hour [Wh] | 3600 |

Kilowatt hour [kWh] | 3600000 |

Erg [erg] | 1e-7 |

Imperial System | |

foot-poundal [ft pdl] | 0.0421401100938 |

inch-pound force [in lbf] | 0.1129848290276167 |

foot-pound force [ft lbf] | 1.3558179483314004 |

horsepower-hour [hph] | 2.6845e+6 |

BTU | 1055.05585262 |

Calories | |

Calories [cal] | 4.1868 |

Kilocalories [kcal] | 4186.8 |

Atomic | |

Electronvolt [eV] | 1.6021765314e-19 |

Hartree [E_{h}] | 4.3597441775e-18 |

Rydberg [Ry] | 2.179872e-18 |