British Thermal Units to Megaelectronvolts (BTU to MeV)
1 British thermal unit equals 6.585140678×10¹⁵ megaelectronvolts (rounded).
How to convert British thermal units to megaelectronvolts
To convert British thermal units to megaelectronvolts, multiply the number of British thermal units by 6.585140678×10¹⁵. The factor is rounded to 10 significant digits. To go the other way, multiply megaelectronvolts by 1.518570443×10⁻¹⁶ (rounded).
megaelectronvolts = British thermal units × 6.585140678×10¹⁵
Example: 10 British thermal units = 6.585140678×10¹⁶ megaelectronvolts.
The 'calorie' on food labels is really a kilocalorie. The thermochemical calorie (4.184 J) is used here unless marked IT.
About these units
British Thermal Unit (BTU)
The International Table BTU, exactly 1,055.05585262 joules. The energy to heat one pound of water by one degree Fahrenheit; used for heating, cooling and gas appliances in the US.
Few energy units come in as many versions as the British thermal unit. It was defined as the heat needed to raise one pound of liquid water by one degree Fahrenheit, but because water's heat capacity shifts slightly with temperature, definitions differ by up to 0.5 percent: about 1,054.35 J for the thermochemical Btu, 1,054.80 J at 59 degrees Fahrenheit (used for American natural gas pricing), 1,054.68 J at 60 degrees (mainly Canadian), and 1,059.67 J at 39 degrees. A 1942 note suggests the term apparently arose in the United States and was later adopted in Britain.
The version on this site is the International Table Btu, about 1,055.06 J, which comes from the international steam table conferences that tied heat units to the joule. Joule's own 1850 experiments gave 772.692 foot-pounds of work per Btu, the number that first linked heat to mechanical effort.
Today the Btu survives in natural gas pricing (MMBtu means a million Btu), US building energy reporting, and equipment ratings in Btu per hour. One ton of air-conditioning is 12,000 Btu/h, or 3.52 kW. A single wooden kitchen match burning releases about one Btu.
1 British thermal unit = 1,055.055853 joules (approximately).
Sources: Wikipedia: British thermal unit; Wikipedia: James Prescott Joule
Megaelectronvolt (MeV)
One million electronvolts. The scale of nuclear reactions.
Nuclei trade energy in millions of electronvolts. In binding-energy tables, medium-mass nuclei hold about 8.8 MeV per nucleon, with iron-56 listed at 8.7906 MeV. Fusing deuterium with tritium releases about 17.53 MeV per reaction, while an electron and positron annihilating give 1.022 MeV. One megaelectronvolt equals 1.602176634 x 10^-13 J, so even these reactions involve only tiny amounts of energy per event.
Per atom, though, the scale is enormous. A 17.53 MeV reaction is more than a million times the 1 to 10 eV that binds atoms into molecules, which is why nuclear fuels hold so much more energy than chemical ones. The electron's rest energy is 0.511 MeV and the muon's is 105.7 MeV, so the unit also serves for particle masses. A thousand MeV make one GeV, the next step up.
1 megaelectronvolt = 1.602176634×10⁻¹³ joules (exactly).
Sources: Wikipedia: Nuclear binding energy; Wikipedia: Electronvolt
Related conversions
- Megaelectronvolts to British thermal units (reverse)
- British thermal units to joules
- British thermal units to kilojoules
- British thermal units to watt-hours
- British thermal units to kilowatt-hours
- British thermal units to calories
- British thermal units to kilocalories
- British thermal units to megajoules
- British thermal units to gigajoules
- British thermal units to megawatt-hours
- British thermal units to foot-pounds
- British thermal units to millijoules
- British thermal units to electronvolts
- Joules to megaelectronvolts
- Kilojoules to megaelectronvolts
- Watt-hours to megaelectronvolts
- Kilowatt-hours to megaelectronvolts
- Calories to megaelectronvolts
- Kilocalories to megaelectronvolts
See all energy units.