12-30-2012: Getting the math right

I have to agree with a fellow writer whom I got to know while attending Launchpad earlier this year - the holiday time sure puts a major crimp in productivity.  (You can see his post here: http://www.matthewsrotundo.com/blog/) I thought I would get some writing done this weekend but only managed less than 1,000 words.  This morning I unexpectedly slept in later than I thought possible and then encountered problems when we got to the bookstore.  Problems?  Like what, you might ask.  Well, since you asked, let me explain.

I prefer to keep the numbers I use in my books as realistic as possible.  For example, if I say I want to be traveling past a certain point at a speed of 15 Km/sec then I had better be correct when I say how much acceleration I will have to apply and for how long to achieve that velocity.  I have a spreadsheet that I rely on to do the math.  Today, I found an error in it and it took me most of an hour to figure out which one of the equations I was using was wrong.  Instead of writing, I spent time fixing the spreadsheet.  Still curious?  Okay - here's how it all went down...

A fleet is poised to attack a planet.  They are stationed 50 million kilometers away.  I first dumped in some numbers wondering how long it would take them to get there at 300G's acceleration.  Simple - divide the distance in half (for acceleration and deceleration time), punch in 300 in my magic spreadsheet, and BINGO, the answer appeared - 3.6 hours.  Multiply that by two for total travel time.  The maximum velocity attained by this calculation was something on the order of 12% light speed.  Too fast for me.  So, I decided to just let them boost at 300G's for an hour and then coast for awhile and then decelerate at 300G's at the other end.  I have a different set of equations for that.  Total travel time turned out to be 1.3 hours - What?  How can using less acceleration get me there faster?  Red alert - red alert - red alert.  Error - Error - Error.  Must analyze.

It took a long time to find the problem and a longer time to run the numbers against several websites to ensure they were correct.  The spreadsheet is now fixed.  If you're interested in the spreadsheet I plan on putting it up on my web page in a few days.

Speaking of my web page.  I will be uploading the new Galactic Alliance covers there as well as my spreadsheet.  I've not had the time to update it recently (the darned holiday again).  Check back in a few days if you're curious.

Happy new year!  I hope 2013 treats everyone well.