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If you ever tell someone that you'll do something in a jiffy, you're probably lying. Surprisingly, a "jiffy" is a real unit of time, equal to how long it takes for light to travel one femtometer, which is one quadrillionth of a meter. In other words, it's really, really brief: A single second contains three hundred thousand billion billion jiffys.
That's the definition of "jiffy" used in physics, but it also has other meanings in the fields of computing and electronics. For example, it can also refer to the length of one cycle of alternating current, which is typically either 1/60 or 1/50 of a second.
Of course, chances are that you're using "jiffy" in the casual sense, as it was first used in the 18th century. If that's the case, it simply means a short amount of time, with short being relative. According to Dictionary.com, the word "jiffy" might have originated with British thieves, who used "jiffy" as slang for "lightning," meaning something very fast. So, you have a choice when using "jiffy": Lie like a scientist or be honest like a thief.
It's about time you learned these facts about time:
- Thanks to Einstein, we know that time passes more slowly for your feet than for your face because your feet are closer to the center of the Earth.
- "Planck time" is the shortest scientific measure of time; it takes trillions and trillions of Planck time to blink once.
- Time seems to get faster as you age because of the "oddball effect," in which new experiences remain in your memory longer than old ones.