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Highway Signs

|< < Prev #3289 (August 24, 2026)

Title text: Highway engineers like Planck units because, like the speed of light, the energy capacity of a typical car's gas tank is 1.

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Explanation

For those who are interested, 0.000000097c is ~104.6 k/h or 65mph. Also, 1.616255e-35 * 1.390e39 is ~22,466m or 14 miles.

The "Next Exit" sign references the Planck Length, which is the (theoretically) smallest possible length. 1.39*10³⁹ Planck lengths is about 13 miles. It would likely be impractical for drivers to count the digits in that sign at highway speeds^{[Citation Needed]}.

Transcript

[Two highway signs stand along a road with mountains in the background. One wide sign reads "NEXT EXIT" above a number starting with 1,390 followed by around thirty six zeros (some zeros are blocked by post of taller sign). A second, taller sign reads "SPEED LIMIT" above the number 0.000000097.]

[Caption below the panel:] OUR LOCAL HIGHWAY DEPARTMENT IS SWITCHING TO PLANCK UNITS.

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