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Classical Mechanics

Fermi Estimation

Concept Quizzes

Fermi Estimates Warmup
Fermi Estimates Economics Applications
Fermi Estimates in Physics

Fermi Estimates in Physics

How many stars are in the observable universe?

10^{8}

10^{22}

10^{36}

10^{50}

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by Brilliant Staff

How many homo sapiens have ever lived?

10 trillion 10 billion 100 billion 1 quintillion

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by Brilliant Staff

How many water molecules are in a human head?

8\times 10^{15}

8\times 10^{25}

8\times 10^{35}

8\times 10^{45}

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by Brilliant Staff

How long has the average United States citizen spent as president?

0.001\text{ seconds}

10\text{ months}

10\text{ hours}

10\text{ seconds}

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by Brilliant Staff

What percent of the observable universe has received radio transmissions from Earth?

10^{-6} \%

10^{-12} \%

10^{-18} \%

10^{-24} \%

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by Brilliant Staff

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