A page of the Numeropedia - the Special Encyclopedia of Numbers
Back to [Numbers 220-229]
[EECS] 220(W, KW or MW) is one of standard numerical values for resistors (of tolerance class 5%). 220pF (picofarads) and 220mF (microfarads) are two of standard numerical values for capacitors.
[Math.] The smallest and only pair of amicable numbers less than 1000 is (220, 284). (From the formula F.7, for n = 1). The first known.
[Math.] The only equation of this form: 140685+62375+50275 = 141325+2205, where its largest entry is less than 20000 (found by Bob Scher, 1995).
[Measure] The number of yards in a furlong.
U.S. customary units for linear measures: 1 mile = 8 furlongs = 320 rods = 1,760 yards = 5,280 feet = 63,360 inches.
[Music] The frequency (Hz, Hertz) of the musical note A (La), below the middle C (Sol): A3 = 220 Hz.
A0 = 27.5 Hz, A1 = 55 Hz, A2 = 110 Hz, A3 = 220 Hz, A4 = 440 Hz, A5 = 880 Hz, A6 = 1760 Hz, A7 = 3520 Hz, A8 = 7040 Hz, A9 = 14,080 Hz and A10 = 28,160 Hz.
[Music] The number of strings in a piano.
[Phone] International telephone dialing code for the Gambia.
[Tech.] The standard voltage of the A.C. electrical power in many countries, except the U.S. is 220 volts or 110 volts. (A.C. = alternating current).
[Theology] The number of sheep (200 female and 20 male) that Jacob gave his brother. (Genesis 32:14).