What is the System of International Units used to represent the measurement of Energy

Energy is divers via work, so the SI unit of free energy is the same as the unit of measurement of piece of work – the joule (J), named in award of James Prescott Joule and his experiments on the mechanical equivalent of heat. In slightly more fundamental terms, 1 joule is equal to ane newton metre and, in terms of SI base of operations units

${\displaystyle 1\ \mathrm {J} =1\ \mathrm {kg} \left({\frac {\mathrm {m} }{\mathrm {s} }}\correct)^{2}=1\ {\frac {\mathrm {kg} \cdot \mathrm {one thousand} ^{2}}{\mathrm {s} ^{2}}}}$

An free energy unit of measurement that is used in atomic physics, particle physics and high energy physics is the electronvolt (eV). One eV is equivalent to 1.602176 634 ×10⁻¹⁹ J.^[1]

In spectroscopy the unit of measurement cm⁻¹ ≈ 0.000123 9842 eV is used to correspond energy since energy is inversely proportional to wavelength from the equation ${\displaystyle E=h\nu =hc/\lambda }$ .

In discussions of energy production and consumption, the units barrel of oil equivalent and ton of oil equivalent are ofttimes used.

British imperial / US customary units [edit]

The British imperial units and U.S. customary units for both energy and work include the pes-pound strength (1.3558 J), the British thermal unit of measurement (BTU) which has various values in the region of 1055 J, the horsepower-hour (2.6845 MJ), and the gasoline gallon equivalent (about 120 MJ).

Electricity [edit]

A unit of electric free energy, peculiarly for utility bills, is the kilowatt-hour (kWh); one kilowatt-hour is equivalent to 3.6 megajoule. Electricity usage is oft given in units of kilowatt-hours per twelvemonth or other time period. This is actually a measurement of average ability consumption, pregnant the average charge per unit at which energy is transferred. One kilowatt-hour per year is about 0.eleven watts.

Natural gas [edit]

Natural gas is often sold in units of energy content or by book. Common units for selling by energy content are joules or therms. One therm is equal to most 1,055 megajoules. Common units for selling by volume are cubic metre or cubic anxiety. Natural gas in the US is sold in therms or 100 cubic feet (100 ft^three = 1 Ccf). In Australia, natural gas is sold in cubic metres. One cubic metre contains nearly 38 megajoules. In the most of the world, natural gas is sold in gigajoules.

Food manufacture [edit]

The calorie is defined as the amount of thermal energy necessary to raise the temperature of one gram of water by 1 Celsius degree, from a temperature of xiv.v °C, at a pressure of one atm. For thermochemistry a calorie of 4.184 J is used, just other calories have also been divers, such every bit the International Steam Table calorie of 4.1868 J. In many regions, food free energy is measured in large calories or kilocalories equalling 1000 calories, sometimes written capitalized as Calories. In the Eu, food energy labeling in joules is mandatory, often with calories as supplementary information.

Atom physics and chemistry [edit]

In physics and chemistry, it is common to measure energy on the diminutive scale in the non-SI, but user-friendly, units electronvolts (eV). 1 eV is equivalent to the kinetic free energy acquired by an electron in passing through a potential departure of 1 volt in a vacuum. It is common to use the SI magnitude prefixes (eg milli- , mega- etc) with electronvolts. Because of the relativistic equivalence between mass and energy, the eV is likewise sometimes used as a unit of mass. The Hartree (the atomic unit of energy) is ordinarily used in calculations.^{[ clarification needed ]} Historically Rydberg units take been used.

Spectroscopy [edit]

In spectroscopy and related fields information technology is common to measure free energy levels in units of reciprocal centimetres. These units (cm^−ane) are strictly speaking not energy units but units proportional to energies, with ${\displaystyle \ hc\sim 2\cdot 10^{-23}\ \mathrm {J} \ \mathrm {cm} }$ being the proportionality constant.^[2]

Explosions [edit]

A gram of TNT releases four,100 to 4,600 joules (980 to ane,100 calories) upon explosion. To define the tonne of TNT, this was standardized to one kilocalorie (four,184 joules) giving a value of 4.184 gigajoules (1 billion calories) for the tonne of TNT.^[3]

Come across besides [edit]

• Energy consumption
• Conversion of units of temperature
• Conversion of units of energy, work, or corporeality of heat
• Listing of unusual units of measurement
• Orders of magnitude (free energy)
• erg
• Foe (unit of measurement)

References [edit]

1. ^ International Agency of Weights and Measures (20 May 2019). The International Organization of Units (SI) (PDF) (9th ed.). Paris: BIPM. ISBN978-92-822-2272-0 . Retrieved 3 Dec 2021.
2. ^ Johnson, R. D., ed. (2002). "CCCBDB What's a cm-i?". Computational Chemistry Comparison and Benchmark DataBase. National Constitute of Standards and Engineering science. doi:10.18434/T47C7Z. Retrieved 2013-11-13 .
3. ^ Thompson, A.; Taylor, B. North., eds. (2019). "Appendix B8—Factors for Units Listed Alphabetically". NIST Guide for the Apply of the International Arrangement of Units (SI). National Institute of Standards and Technology (9th ed.).

keimtindin.blogspot.com

Source: https://en.wikipedia.org/wiki/Units_of_energy

Share this post