Essay Question: What are some things that you can do now to make
the most of that third of a million pushups* worth of ordered
energy, if indeed it's there, in each gallon of fossil-fuel
gasoline (non-renewable) that you use?
- What guidelines for use of your
automobile might make each gallon go a bit further?
- What's most usefully done with your gasoline engine
while waiting for fast food?
- Which uses more gasoline: Holding speed constant or rapidly accelerating?
- What things (e.g. racks, open windows)
affect the energy your car
dissipates in its turbulent
wake at high speed?
- Can you choose paths from point A to B which
make those Calories in your gas tank last longer?
- How do driving time, distance, and speed all figure in?
- Does going up hills and down hills, or do stop signs, have
a significant impact on the energy one wastes?
- Which impacts mileage more: air conditioner on,
fan on, lights on, or cell phone recharge through the lighter jack?
- Are there things other than fossil fuel that you can
put in your gas tank to help out?
- Would dimples in your car's finish-coat help, like they do on a golf ball?
Or tennis ball fuzz?
- How much do tires low on air, and extra junk in the trunk,
add to your mileage?
- Do some cars take gasoline's energy and do more with it
than others, before the energy is turned into ambient heat?
- Is your car optimizing the fuel-air mixture to
ensure complete combustion, and to control
byproducts as well?
- Where at in the combustion chamber is your
fuel being injected, and how might that help out?
- Does compression ratio, or burn temperature, have
a role to play here?
- What cars have regenerative braking, and how
much further does this make a gallon of gasoline go?
- In what rpm ranges are car engines most efficient,
and are some cars designed with these ranges in mind?
- Is there value in converting energy from
gasoline into electricity (or something
else) rather than using it to drive?
- How does the efficiency of gas fired power plants
compare to that of Otto or Diesel combustion engines?
- What are the strengths and weaknesses of today's
plugin hybrids and electric cars?
- What assumptions constrain that assertion
about a gallon of gasoline and a third of a
- Do folks with greater weight and longer
limbs require more energy to do a pushup
- Does the calculation consider respiration
energy, as well as energy required for the lift?
- What are likely averages, and standard deviations,
for a pushup's energy in the population at large?
- Would increases in gravity, air pressure, or
surface springiness affect the work required?
- How does one determine the work available from
a molecule (or gallon) of
- How might questions like this be posed
to help the reader discover informed
creative answers in a finite time?
- Would lists, like this, of possible follow-on
directions come in handy?
* Assume 114100 BTUs or 1.2×108 Joules in a
gallon of regular gasoline, and that a pushup involves lifting
a weight if 80 kg × 9.8 m/sec2 a distance
of 1 meter. The pushup then requires 392 Joules, and dividing
this into the gasoline energy gives 307097 pushups per gallon.