These engineering and science tech-centric
jokes, song parodies, anecdotes and assorted humor have been collected from friends
and websites across the Internet. I check back occasionally for new fodder, but
it seems all the old content is reappearing all over (like this is). The humor is
light-hearted and clean and sometimes slightly assaultive to the easily-offended,
so you are forewarned. It is all workplace-safe.
So, how many AA batteries would it
take to power a standard adult human for one day?
A Manganese/Alkaline AA cell it rated at about
2.4 amp-hours. If we assume 1.5 volts average this gives approximately 3.6 watt-hours (slightly optimistic). Since
there are 3,600 seconds in an hour this is equivalent to 12,960 Joules.
A human consumes about 2,000 calories/day. A dietician calorie is equal to 1,000 engineering calories. A calorie
is equal to 4.2 Joules. Therefore this is equivalent to 2,000 * 1,000 * 4.2 = 8.4 * 106 Joules per day.
Dividing one by the other you will need about 648 AA cells to power a human for one day.
This assumes that
the power from the AA cell will go through the same inefficiencies as the chemical processes in a human. (A human
runs at about 20% efficiency chemical energy to mechanical energy). If we can circumvent this inefficiency we
would only need 20% of this number of cells - say 130 cells.
---From: Ben Gebeau
Related Pages on RF Cafe:
or Li-Poly Battery Characteristics
Inside a 9-Volt Battery
How Many AA Batteries Would to Take to Power a Human?
- Ray-O-Vac Ad, August 25, 1945, Saturday Evening Post