2021 Fermi Questions

The great twentieth century physicist Enrico Fermi was famous for being able to estimate anything to within a factor of ten. Examples of “Fermi Questions” are:

  • What is the total mass of the students competing in the Physics Olympics today?
  • How many litres of gasoline are consumed in Greater Vancouver each year?
  • How many molecules of air are there in this room?

For more examples, look on the web. These were taken from http://www.physics.uwo.ca/science_olympics/events/puzzles/fermi_questions.html (Links to an external site.)

Answering a Fermi question in physics requires common sense understanding, knowing the order of magnitude of key constants of nature and physical parameters, and the ability to do approximate calculations quickly.

Your team will be given a number of Fermi Questions to answer using only pencil and paper and your own knowledge. No notes, tables, books, or calculators are allowed. Cellphones, tablets or computers are only allowed to communicate with your teammates and to access the Canvas site. Since there will be a substantial number of questions to answer and only a limited time to answer them, speed and teamwork will be important. Your written answers will be graded for accuracy appropriate to the questions. Your answers must include appropriate units, in the SI (MKS) system.

Many physicists pride themselves on knowing various constants of nature and physical parameters to at least one decimal place. Parameters that may be needed, to this accuracy, include but are not limited to:

  • the speed of light
  • Planck’s constant
  • Boltzmann’s constant
  • Avogadro’s number
  • the mass of the electron
  • the mass of the proton
  • the charge of the electron
  • the constant in Coulomb’s Law
  • the constant in Newton’s Law of Universal Gravitation
  • the acceleration of gravity on Earth
  • the radius of the Earth, and
  • the distance from Earth to the Sun