equivalent focal length
optics the ratio of the size of an image of a small distant object near the optical axis to the angular distance of the object in radians
Did One Man Write The First Great English Dictionary All By Himself?We’d like to take a moment to celebrate the man behind A Dictionary of the English Language, the first definitive English dictionary, the famous Samuel Johnson.
Digging Up Old Slang For Body PartsRead more in this article about some frequently asked questions and fun facts related to our definitions.
- equivalence relation,
- equivalent air speed,
- equivalent circuit,
- equivalent weight,
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