Quote:
Originally Posted by sjastro
Sorry to be nitpicky Carl. 
While the magnitude of the answer is correct it is expressed in km.day. not km.
To cancel out the day unit, work out the number of sheets "n" in the stack instead.
This is simply (4.56 X 10^9 X 365)/1 = 1.664 X 10^12
While dividing by one (one day) seems trivial, the number "n" is a dimensionless quantity. Multiplying "n" by thickness gives the correct unit.
Regards
Steven |
You've been missing the implied unit in the paper. 1 sheet per day.
thickness of 1 sheet * sheets/day * days/year * years all cancels leaving whatever linear unit the sheet thickness is in.
The assumption for days/year (365, 365.25 Julian calendar, 365.2425 Gregorian calendar, 365.242189 mean tropical year for 2000 according to Laskar) mean whatever value you come up with can only be an estimate.
And there's no allowance for the changes caused by the impact that created the moon (which would have made a large change), or meteor/asteroid/comet impacts, or tidal slowing of the rotation.
But it's an amusing interlude.