# Special Numbers in The Metric System

Here are some special and interesting numbers in the Metric System:

Quantity | Approximate Value | Notes |
---|---|---|

Speed of light (in vacuum) | 300 000 000 m/s | 3 x 10^{8} in Scientific NotationMore accurately 299 792 458 m/s |

Speed of sound (in air) | 340 m/s | Varies with temperature and pressure |

Earth's gravity | 9.8 m/s^{2} |
Varies by location |

Distance from Earth to Sun | 150 000 000 km | Varies over the year |

Distance from Earth to Moon | 384 000 km | Varies |

Circumference of Earth |
40 000 km | |

Height of Mount Everest | 8849 m | |

Height of geostationary satellite |
35 800 km | |

Freezing point of water | 0°C | Varies with pressure |

Human body temperature | 37°C | Varies by person, site and health |

Boiling point of water | 100°C | Varies with pressure |

Atmospheric pressure | 100 kPa | Varies with weather and height |

Density of water | 1 g/cm^{3}(= 1 kg per liter) |
Varies with temperature and pressure |

Density of rock | 3 g/cm^{3} |
Varies a lot based on type of rock |

Density of gold | 19.3 g/cm^{3} |