1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Gravitational constanT G - HELP!

  1. Jun 6, 2004 #1
    gravitational constanT G -- HELP!

    :yuck:

    ok, right now I'm working on a physics project :) satelite motion around earth...I managed to create a program that simulates all that stuff...but I don't quite like my G constant!

    In my program I want to recreate moon and earth relationship!

    so scale looks this way:
    1pixel = 1829773.7957659496946338217168068 meters

    so now I want my G number to be written in pixels, I know it's m*m*m/kg * s * s

    so, I can't make up my mind, how to write that in pixels...:)

    any help appreciated :)
     
    Last edited: Jun 6, 2004
  2. jcsd
  3. Jun 6, 2004 #2
    You can do it by dimensional analysis. Just treat a pixel as just another unit of length, as if you were going to convert G from SI units to British units.

    First, let b = 1829773.7957659496946338217168068, where your conversion factor is "b meters per pixel." Additionally, I'm going to write G = 6.673*10^-11 m^3/(kg*s^2) here, but you should use a value to however many decimals you wish.

    So:

    [tex]
    \newcommand{\unit}[1]{\mathrel{\mathrm{#1}}}
    G = \frac{6.673\times 10^{-11}\unit{m^3}}{\unit{kg\cdot s^2}}\cdot
    \frac{\unit{pixel^3}}{(b\unit{m})^3}
    [/tex]

    Therefore, your new value of the gravitational constant is:

    [tex]
    \newcommand{\unit}[1]{\mathrel{\mathrm{#1}}}
    G = \frac{6.673\times 10^{-11}\unit{pixel^3}}{b^3\unit{kg\cdot s^2}}
    \approx \frac{1.089\times 10^{-29}\unit{pixel^3}}{\unit{kg\cdot s^2}}
    [/tex]

    To make a long story short, divide by 1829773.7957659496946338217168068^3.
     
    Last edited: Jun 6, 2004
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Gravitational constanT G - HELP!
  1. G formula? (Replies: 12)

Loading...