Angle

1 revolution = 2π = 360°

 Solid Angle

1 sphere = 4π steradians (sr) = 4.1253 × 10⁴ square degrees

 Length

1 inch = 2.54 × 10^-2 m

1 foot (ft) = 12 inch = 0.3048 m

1 yard = 3 ft = 0.9144 m

1 statute mile = 5280 ft = 1609 m

1 nautical mile = 6080 ft = 1853 m

1 Angstrom (Å) = 10^-10 m

1 Fermi = 10^-15 m

1 lightyear = 9.460530 × 10¹⁵ m

1 Astronomical Unit (AU) = 1.495979 × 10¹¹ m

1 parsec (pc) = 1 AU/tan (1") = 3.085678 × 10¹⁶ m

1 solar radius (R) = 6.9599 × 10⁸ m

 Area

1 hectare = 10⁴ m²

1 acre = 43560 ft² = 4046.9 m²

1 barn = 10^-28 m²

 Frequency

1 Hertz (Hz) = 1 s^-1

 Speed

1 knot = 1 nautical mile/hour = 1.8532 km h^-1 = 0.5147 m s^-1

1 mile/hour = 1.6093 km h^-1 = 0.4470 m s^-1

 Mass

1 pound (lb) = 0.45359237 kg

1 atomic mass unit (u) = 1.66057 × 10^-27 kg

1 solar mass (M) = 1.989 × 10³⁰ kg

 Force

1 Newton (N) = 1 kg m s^-2

1 dyne = 10^-5 N

1 pound (lb) = 4.44822 N

 Pressure

1 Pascal (Pa) = 1 N m^-2

1 atmosphere = 1.013 × 10⁵ Pa

1 bar = 10⁵ Pa

1 torr = 1 mm Hg at 0° and standard gravity = 133.322 Pa

 Energy

1 Joule (J) = 1 N m = 1 W s

1 erg = 10^-7 J

1 Calorie = 4186 J

1 kiloton TNT = 4.2 × 10¹² J

1 electronvolt (eV) = 1.602189 × 10^-19 J

 Power

1 Watt (W) = 1 J s^-1 = 1 V A

1 Horse Power (hp) = 745.7 W

1 solar luminosity (L) = 3.826 × 10²⁶ W

 Electric charge

1 Coulomb (C) = 1 A s

1 elementary charge (e) = 1.602189 × 10^-19 C

 Electric potential

1 Volt (V) = 1 W A^-1

 Electric resistance

1 Ohm (Ω) = 1 V A^-1

 Electric capacitance

1 Farad (F) = 1 C V^-1

 Conductance

1 Siemens (S) = 1 A V^-1

 Inductace

1 Henry (H) = 1 Wb A^-1

 Magnetic flux

1 Weber (Wb) = 1 V s^-1

 Magnetic field strength

1 Tesla (T) = 1 N A^-1 m^-1 = 1 Wb m^-2

1 gauss = 10^-4 T

 Flux density

1 Jansky (Jy) = 10^-26 W m^-2 s

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