How many attojoule in 1 British thermal unit?
The answer is 1.0550559E+21.
We assume you are converting between attojoule and British thermal unit.
You can view more details on each measurement unit: attojoule or
British thermal unit
The SI derived unit for energy is the joule.
1 joule is equal to 1.0E+18 attojoule, or 0.00094781707774915 British thermal unit.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between attojoules and Btus.
Type in your own numbers in the form to convert the units!

The SI prefix "atto" represents a factor of
10^{-18}, or in exponential notation, 1E-18.

So 1 attojoule = 10^{-18} joules.

The definition of a joule is as follows:

The joule (symbol J, also called newton meter, watt second, or coulomb volt) is the SI unit of energy and work. The unit is pronounced to rhyme with "tool", and is named in honor of the physicist James Prescott Joule (1818-1889).

››Definition: Btu

The British thermal unit (BTU or Btu) is a non-metric unit of energy, used in the United States and, to a lesser extent, the UK (where it isgenerally only used for heating systems). The SI unit is the joule (J), which is used by most other countries.

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