Friday, December 4, 2009

Liquid Sugar (FPOTW)

A friend and I were walking around the mall waiting for the movie theater to open. We were lamenting how much the tickets would cost, and formulating plans to smuggle food into the theater. Why in the hell should we spend more on the snacks than on the tickets? Like a flash out of the blue a Fermi problem presented itself to help us while away the time:

---- Start Fermi Problem ----

How much soda pop do Americans drink each day?

If you could put all that soda into a cubic container, what would the containers dimensions be?

How much sugar energy is represented?

How long would that energy power an average home?

---- End Fermi Problem ----

As is usual for a Fermi problem, we are only concerned with accuracy of an order of magnitude.
You can look up certain numbers such as kilo calories per gram of sugar if you don't know it, but in a Fermi problem one should use common sense and reasonable guesses rather than looking up numbers. And since most of you do not carry a calculator around everywhere, you should be facile with numbers.

Sunday, November 29, 2009

Fat of the Land (FPOTW)

Ugg... I am stuffed! All that turkey, all that food. =(   =)

I was reading an article in CNN about the percentage of overweight and
obese people in the good old USA. The pundits and experts agree that 65%
of Americans are overweight, and 30% are obese.

---- Start Fermi Problem ----

If you were to liposuction the excess fat off of Americans, estimate how much you would get.

If you could burn the fat for energy, for how long could you power an average home?

---- End Fermi Problem ----

The radical Muslims could now say: "Kill all Americans, and burn them for electricity!"