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Dr. Shapiro's Puzzle of the Day

Today's Puzzle

Thursday, March 11
℧ is a common symbol for a unit of electrical conductance, defined as the reciprocal of 1 ohm. The official name for this unit is the siemens. However, what shorter name is also used?

Hint Outside of a room where physics is being discussed, this word is most likely to show up in a crossword puzzle. Such as...

   


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Yesterday's Puzzle + Solution

M I L D not picante ill-formed
_ _ _ _ pickling herb ill-formed
_ _ _ _ _ copycat ill-formed
_ _ _ _ _ polite ill-formed
_ _ _ _ _ pale, perhaps with rage ill-formed
_ _ _ _ _   lifelike, or evoking strong images   ill-formed
_ _ _ word from a recipe well-formed

Solution These are words that look like Roman numerals, in that they only contain the letters MDCLXVI. However, only the last word is a legitimate numeral. The words are DILL, MIMIC, CIVIL, LIVID, VIVID, and MIX (which represents 1009).

Congratulations to yesterday's winners Inca, Jacob C., Graham, and Mr. and Mrs. Gregg. Thanks to everybody who made a guess!

About This Site

Though he now teaches mathematics, Dr. (né Mr.) Shapiro's first job in a K–12 school was as a lunch monitor in Davis, CA. It was there that he originated the Puzzle of the Day, even rewarding correct answers with tickets in denominations like "15 points" (though without a clear idea of how he'd ultimately redeem these). Dr. Shapiro's favorite puzzle from this pre-professional era was "Tell me the location of the beehive on this campus."

Ten years later, Dr. Shapiro revived Puzzle of the Day at Proof School, writing each day's puzzle on a name tag. After 600 puzzles or so, he was just starting to feel normal about students reading his chest all the time when campus closed and the puzzle, like the rest of our lives, moved online. New puzzles are posted daily on school days.

Want to catch up on old PotDs? There's an archive currently containing puzzles from March to December 2020.