Nikiya Anton Bettey 2021: 09-26-2021-2237

Monday, September 27, 2021

09-26-2021-2237 - energy density

Beyond the Ball: 10 Unique Disco Ball Designs

In physics, energy density is the amount of energy stored in a given system or region of space per unit volume. It may also be used for energy per unit mass, though a more accurate term for this is specific energy(or gravimetric energy density).

Often only the useful or extractable energy is measured, which is to say that inaccessible energy (such as rest mass energy) is ignored.^[1] In cosmological and other general relativistic contexts, however, the energy densities considered are those that correspond to the elements of the stress–energy tensor and therefore do include mass energy as well as energy densities associated with the pressures described in the next paragraph.

Energy per unit volume has the same physical units as pressure, and in many circumstances is a synonym: for example, the energy density of a magnetic field may be expressed as (and behaves as) a physical pressure, and the energy required to compress a compressed gas a little more may be determined by multiplying the difference between the gas pressure and the external pressure by the change in volume. A pressure gradient has the potential to perform work on the surroundings by converting internal energy to work until equilibrium is reached.

Energy density
SI unit	J/m³
Other units	J/L, W⋅h/L
In SI base units	m⁻¹⋅kg⋅s⁻²
Derivations from other quantities	U = E/V
Dimension	${\mathsf {L}}^{-1}{\mathsf {M}}{\mathsf {T}}^{-2}$

List of material energy densities[edit]

This article or section appears to contradict itself. Please see the talk page for more information. (April 2019)

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The following unit conversions may be helpful when considering the data in the tables: 3.6 MJ = 1 kW⋅h ≈ 1.34 hp⋅h. Since 1 J = 10⁻⁶ MJ and 1 m³ = 10³ L, divide joule/m³ by 10⁹ to get MJ/L = GJ/m³. Divide MJ/L by 3.6 to get kW⋅h/L.

In nuclear reactions[edit]

Energy released by nuclear reactions
Material	Specific energy (MJ/kg)	Energy density (MJ/L)	Specific energy (W⋅h/kg)	Energy density (W⋅h/L)	Comment
Antimatter	89,875,517,874 ≈ 90 PJ/kg	Depends on the density of the antimatter's form	24,965,421,631,578 ≈ 25 TW⋅h/kg	Depends on the density of the antimatter's form	Annihilation, counting both the consumed antimatter mass and ordinary matter mass
Hydrogen(fusion)	639,780,320^[15] but at least 2% of this is lost to neutrinos.	Depends on conditions	177,716,755,600	Depends on conditions	Reaction 4H→⁴He
Deuterium(fusion)	571,182,758^[16]	Depends on conditions	158,661,876,600	Depends on conditions	Proposed fusion scheme for D+D→⁴He, by combining D+D→T+H, T+D→⁴He+n, n+H→D and D+D→³He+n, ³He+D→⁴He+H, n+H→D
Deuterium+tritium(fusion)	337,387,388^[15]	Depends on conditions	93,718,718,800	Depends on conditions	D + T → ⁴He + n Being developed.
Lithium-6 deuteride (fusion)	268,848,415^[15]	Depends on conditions	74,680,115,100	Depends on conditions	⁶LiD → 2⁴He Used in weapons.
Plutonium-239	83,610,000	1,300,000,000–1,700,000,000 (Depends on crystallographic phase)	23,222,915,000	370,000,000,000–460,000,000,000 (Depends on crystallographic phase)	Heat produced in Fission reactor
Plutonium-239	31,000,000	490,000,000–620,000,000 (Depends on crystallographic phase)	8,700,000,000	140,000,000,000–170,000,000,000 (Depends on crystallographic phase)	Electricity produced in Fission reactor
Uranium	80,620,000^[17]	1,539,842,000	22,394,000,000		Heat produced in breeder reactor
Thorium	79,420,000^[17]	929,214,000	22,061,000,000		Heat produced in breeder reactor(Experimental)
Plutonium-238	2,239,000	43,277,631	621,900,000		Radioisotope thermoelectric generator. The heat is only produced at a rate of 0.57 W/g.

In chemical reactions (oxidation)[edit]

Unless otherwise stated, the values in the following table are lower heating values for perfect combustion, not counting oxidizer mass or volume. When used to produce electricity in a fuel cell or to do work, it is the Gibbs free energy of reaction (ΔG) that sets the theoretical upper limit. If the produced H
2O is vapor, this is generally greater than the lower heat of combustion, whereas if the produced H
2O is liquid, it is generally less than the higher heat of combustion. But in the most relevant case of hydrogen, ΔG is 113 MJ/kg if water vapor is produced, and 118 MJ/kg if liquid water is produced, both being less than the lower heat of combustion (120 MJ/kg).^[18]

Energy released by chemical reactions (oxidation)
Material	Specific energy (MJ/kg)	Energy density (MJ/L)	Specific energy (W⋅h/kg)	Energy density (W⋅h/L)	Comment
Hydrogen, liquid	141.86 (HHV) 119.93 (LHV)	10.044 (HHV) 8.491 (LHV)	39,405.6 (HHV) 33,313.9 (LHV)	2,790.0 (HHV) 2,358.6 (LHV)	Energy figures apply after reheating to 25 °C.^[19] See note above about use in fuel cells.
Hydrogen, gas (69 MPa, 25 °C)	141.86 (HHV) 119.93 (LHV)	5.323 (HHV) 4.500 (LHV)	39,405.6 (HHV) 33,313.9 (LHV)	1,478.6 (HHV) 1,250.0 (LHV)	Date from same reference as for liquid hydrogen.^[19] High-pressure tanks weigh much more than the hydrogen they can hold. The hydrogen may be around 5.7% of the total mass,^[20] giving just 6.8 MJ per kg total mass for the LHV. See note above about use in fuel cells.
Hydrogen, gas (1 atm or 101.3 kPa, 25 °C)	141.86 (HHV) 119.93 (LHV)	0.01188 (HHV) 0.01005 (LHV)	39,405.6 (HHV) 33,313.9 (LHV)	3.3 (HHV) 2.8 (LHV)	^[19]
Diborane	78.2		21,722.2		^[21]
Beryllium	67.6	125.1	18,777.8	34,750.0
Lithium borohydride	65.2	43.4	18,111.1	12,055.6
Boron	58.9	137.8	16,361.1	38,277.8	^[22]
Methane (101.3 kPa, 15 °C)	55.6	0.0378	15,444.5	10.5
LNG (NG at −160 °C)	53.6^[23]	22.2	14,888.9	6,166.7
CNG (NG compressed to 25 MPa ≈ 3600 psi)	53.6^[23]	9	14,888.9	2,500.0
Natural gas	53.6^[23]	0.0364	14,888.9	10.1
LPG propane	49.6	25.3	13,777.8	7,027.8	^[24]
LPG butane	49.1	27.7	13,638.9	7,694.5	^[24]
Gasoline (petrol)	46.4	34.2	12,888.9	9,500.0	^[24]
Polypropylene plastic	46.4^[25]	41.7	12,888.9	11,583.3
Polyethylene plastic	46.3^[25]	42.6	12,861.1	11,833.3
Residential heating oil	46.2	37.3	12,833.3	10,361.1	^[24]
Diesel fuel	45.6	38.6	12,666.7	10,722.2	^[24]
100LL Avgas	44.0^[26]	31.59	12,222.2	8,775.0
Jet fuel (e.g. kerosene)	43^[27]^[28]^[29]	35			Aircraft engine
Gasohol E10 (10% ethanol 90% gasoline by volume)	43.54	33.18	12,094.5	9,216.7
Lithium	43.1	23.0	11,972.2	6,388.9
Biodiesel oil (vegetable oil)	42.20	33	11,722.2	9,166.7
DMF (2,5-dimethylfuran)	42^[30]	37.8	11,666.7	10,500.0	^{[clarification needed]}
Crude oil (tonne of oil equivalent)	41.868	37^[23]	11,630	10,278
Polystyrene plastic	41.4^[25]	43.5	11,500.0	12,083.3
Body fat	38	35	10,555.6	9,722.2	Metabolism in human body (22% efficiency^[31])
Butanol	36.6	29.2	10,166.7	8,111.1
Gasohol E85 (85% ethanol 15% gasoline by volume)	33.1	25.65^{[citation needed]}	9,194.5	7,125.0
Graphite	32.7	72.9	9,083.3	20,250.0
Coal, anthracite	26–33	34–43	7,222.2–9,166.7	9,444.5–11,944.5	Figures represent perfect combustion not counting oxidizer, but efficiency of conversion to electricity is ≈36%^[7]
Silicon	1.790	4.5	500	1,285	Energy stored through solid to liquid phase change of silicon^[32]
Aluminium	31.0	83.8	8,611.1	23,277.8
Ethanol	30	24	8,333.3	6,666.7
DME	31.7 (HHV) 28.4 (LHV)	21.24 (HHV) 19.03 (LHV)	8,805.6 (HHV) 7,888.9 (LHV)	5,900.0 (HHV) 5,286.1 (LHV)	^[33]^[34]
Polyester plastic	26.0^[25]	35.6	7,222.2	9,888.9
Magnesium	24.7	43.0	6,861.1	11,944.5
Coal, bituminous	24–35	26–49	6,666.7–9,722.2	7,222.2–13,611.1	^[7]
PET plastic (impure)	23.5^[35]		6,527.8
Methanol	19.7	15.6	5,472.2	4,333.3
Hydrazine (combusted to N₂+H₂O)	19.5	19.3	5,416.7	5,361.1
Liquid ammonia(combusted to N₂+H₂O)	18.6	11.5	5,166.7	3,194.5
PVC plastic (improper combustion toxic)	18.0^[25]	25.2	5,000.0	7,000.0	^{[clarification needed]}
Wood	18.0		5,000.0		^[36]
Peat briquette	17.7		4,916.7		^[37]
Sugars, carbohydrates, and protein	17	26.2 (dextrose)	4,722.2	7,277.8	Metabolism in human body (22% efficiency^[38])^{[citation needed]}
Calcium	15.9	24.6	4,416.7	6,833.3	^{[citation needed]}
Glucose	15.55	23.9	4,319.5	6,638.9
Dry cow dung and camel dung	15.5^[39]		4,305.6
Coal, lignite	10–20		2,777.8–5,555.6		^{[citation needed]}
Sodium	13.3	12.8	3,694.5	3,555.6	burned to wet sodium hydroxide
Peat	12.8		3,555.6
Nitromethane	11.3		3,138.9
Sulfur	9.23	19.11	2,563.9	5,308.3	burned to sulfur dioxide^[40]
Sodium	9.1	8.8	2,527.8	2,444.5	burned to dry sodium oxide
Battery, lithium-air rechargeable	9.0^[41]		2,500.0		Controlled electric discharge
Household waste	8.0^[42]		2,222.2
Zinc	5.3	38.0	1,472.2	10,555.6
Iron	5.2	40.68	1,444.5	11,300.0	burned to iron(III) oxide
Teflon plastic	5.1	11.2	1,416.7	3,111.1	combustion toxic, but flame retardant
Iron	4.9	38.2	1,361.1	10,611.1	burned to iron(II) oxide
Gunpowder	4.7–11.3^[43]	5.9–12.9
TNT	4.184	6.92
ANFO	3.7		1,027.8

Other release mechanisms[edit]

Energy released by electrochemical reactions or other means
Material	Specific energy (MJ/kg)	Energy density (MJ/L)	Specific energy (W⋅h/kg)	Energy density (W⋅h/L)	Comment
Battery, zinc-air	1.59	6.02	441.7	1,672.2	Controlled electric discharge^[44]
Liquid nitrogen	0.77^[45]	0.62	213.9	172.2	Maximum reversible work at 77.4 K with 300 K reservoir
Sodium sulfur battery	0.54–0.86		150–240
Compressed air at 30 MPa	0.5	0.2	138.9	55.6	Potential energy
Latent heat of fusion of ice^{[citation needed]} (thermal)	0.33355	0.33355	93.1	93.1
Lithium metal battery	1.8	4.32			Controlled electric discharge
Lithium-ion battery	0.36–0.875^[48]	0.9–2.63	100.00–243.06	250.00–730.56	Controlled electric discharge
Flywheel	0.36–0.5	5.3			Potential energy
Alkaline battery	0.48^[49]	1.3^[50]			Controlled electric discharge
Nickel-metal hydride battery	0.41^[51]	0.504–1.46^[51]			Controlled electric discharge
Lead-acid battery	0.17	0.56			Controlled electric discharge
Supercapacitor (EDLC)	0.01–0.030^[52]^[53]^[54]^[55]^[56]^[57]^[58]	0.006–0.06^[52]^[53]^[54]^[55]^[56]^[57]	up to 8.57^[58]		Controlled electric discharge
Water at 100 m dam height	0.000981	0.000978	0.272	0.272	Figures represent potential energy, but efficiency of conversion to electricity is 85–90%^[59]^[60]
Electrolytic capacitor	0.00001–0.0002^[61]	0.00001–0.001^[61]^[62]^[63]			Controlled electric discharge

In material deformation[edit]

The mechanical energy storage capacity, or resilience, of a Hookean material when it is deformed to the point of failure can be computed by calculating tensile strength times the maximum elongation dividing by two. The maximum elongation of a Hookean material can be computed by dividing stiffness of that material by its ultimate tensile strength. The following table lists these values computed using the Young's modulus as measure of stiffness:

Mechanical energy capacities
Material	Energy density by mass (J/kg)	Resilience: Energy density by volume (J/L)	Density (kg/L)	Young's modulus (GPa)	Tensile yield strength (MPa)
Rubber band	1,651–6,605^[64]	2,200–8,900^[64]	1.35^[64]
Steel, ASTM A228 (yield, 1 mm diameter)	1,440–1,770	11,200–13,800	7.80^[65]	210^[65]	2,170–2,410^[65]
Acetals	908	754	0.831^[66]	2.8^[67]	65 (ultimate)^[67]
Nylon-6	233–1,870	253–2,030	1.084	2–4^[67]	45–90 (ultimate)^[67]
Copper Beryllium 25-1/2 HT (yield)	684	5,720^[68]	8.36^[69]	131^[68]	1,224^[68]
Polycarbonates	433–615	520–740	1.2^[70]	2.6^[67]	52–62 (ultimate)^[67]
ABS plastics	241–534	258–571	1.07	1.4–3.1^[67]	40 (ultimate)^[67]
Acrylic		1,530		3.2^[67]	70 (ultimate)^[67]
Aluminium 7077-T8 (yield)	399	1120^[68]	2.81^[71]	71.0^[68]	400^[68]
Steel, stainless, 301-H (yield)	301	2,410^[68]	8.0^[72]	193^[68]	965^[68]
Aluminium 6061-T6 (yield @ 24 °C)	205	553	2.70^[73]	68.9^[73]	276^[73]
Epoxy resins		113–1810		2–3^[67]	26–85 (ultimate)^[67]
Douglas fir Wood	158–200	96	.481–.609^[74]	13^[67]	50 (compression)^[67]
Steel, Mild AISI 1018	42.4	334	7.87^[75]	205^[75]	370 (440 Ultimate)^[75]
Aluminium (not alloyed)	32.5	87.7	2.70^[76]	69^[67]	110 (ultimate)^[67]
Pine (American Eastern White, flexural)	31.8–32.8	11.1–11.5	.350^[77]	8.30–8.56 (flexural)^[77]	41.4 (flexural)^[77]
Brass	28.6–36.5	250–306	8.4–8.73^[78]	102–125^[67]	250 (ultimate)^[67]
Copper	23.1	207	8.93^[78]	117^[67]	220 (ultimate)^[67]
Glass	5.56–10.0	13.9–25.0	2.5^[79]	50–90^[67]	50 (compression)^[67]

In batteries[edit]

Battery energy capacities
Storage device	Energy content (Joule)	Energy content (W⋅h)	Energy type	Typical mass (g)	Typical dimensions (diameter × height in mm)	Typical volume (mL)	Energy density by volume (MJ/L)	Energy density by mass (MJ/kg)
Alkaline AA battery^[80]	9,360	2.6	Electrochemical	24	14.2 × 50	7.92	1.18	0.39
Alkaline C battery^[80]	34,416	9.5	Electrochemical	65	26 × 46	24.42	1.41	0.53
NiMH AA battery	9,072	2.5	Electrochemical	26	14.2 × 50	7.92	1.15	0.35
NiMH C battery	19,440	5.4	Electrochemical	82	26 × 46	24.42	0.80	0.24
Lithium-ion 18650 battery	28,800–46,800	10.5–13	Electrochemical	44–49^[81]	18 × 65	16.54	1.74–2.83	0.59–1.06

Nuclear energy sources[edit]

The greatest energy source by far is mass itself. This energy, E = mc², where m = ρV, ρ is the mass per unit volume, V is the volume of the mass itself and c is the speed of light. This energy, however, can be released only by the processes of nuclear fission (0.1%), nuclear fusion (1%), or the annihilation of some or all of the matter in the volume V by matter-antimatter collisions (100%).^{[citation needed]} Nuclear reactions cannot be realized by chemical reactions such as combustion. Although greater matter densities can be achieved, the density of a neutron star would approximate the most dense system capable of matter-antimatter annihilation possible. A black hole, although denser than a neutron star, does not have an equivalent anti-particle form, but would offer the same 100% conversion rate of mass to energy in the form of Hawking radiation. In the case of relatively small black holes (smaller than astronomical objects) the power output would be tremendous.

The highest density sources of energy aside from antimatter are fusion and fission. Fusion includes energy from the sun which will be available for billions of years (in the form of sunlight) but so far (2021), sustained fusion power production continues to be elusive.

Power from fission of uranium and thorium in nuclear power plants will be available for many decades or even centuries because of the plentiful supply of the elements on earth,^[82] though the full potential of this source can only be realized through breeder reactors, which are, apart from the BN-600 reactor, not yet used commercially.^[83] Coal, gas, and petroleum are the current primary energy sources in the U.S.^[84] but have a much lower energy density. Burning local biomass fuels supplies household energy needs (cooking fires, oil lamps, etc.) worldwide.

Thermal power of nuclear fission reactors[edit]

The density of thermal energy contained in the core of a light water reactor (PWR or BWR) of typically 1 GWe (1 000 MW electrical corresponding to ≈3 000 MW thermal) is in the range of 10 to 100 MW of thermal energy per cubic meter of cooling water depending on the location considered in the system (the core itself (≈30 m³), the reactor pressure vessel (≈50 m³), or the whole primary circuit (≈300 m³)). This represents a considerable density of energy which requires under all circumstances a continuous water flow at high velocity in order to be able to remove the heat from the core, even after an emergency shutdown of the reactor. The incapacity to cool the cores of three boiling water reactors (BWR) at Fukushima in 2011 after the tsunami and the resulting loss of the external electrical power and of the cold source was the cause of the meltdown of the three cores in only a few hours, even though the three reactors were correctly shut down just after the Tōhoku earthquake. This extremely high power density distinguishes nuclear power plants (NPP's) from any thermal power plants (burning coal, fuel or gas) or any chemical plants and explains the large redundancy required to permanently control the neutron reactivity and to remove the residual heat from the core of NPP's.

Energy density of electric and magnetic fields[edit]

Electric and magnetic fields store energy. In a vacuum, the (volumetric) energy density is given by

u={\frac {\varepsilon _{0}}{2}}\mathbf {E} ^{2}+{\frac {1}{2\mu _{0}}}\mathbf {B} ^{2}

where E is the electric field and B is the magnetic field. The solution will be (in SI units) in Joules per cubic metre. In the context of magnetohydrodynamics, the physics of conductive fluids, the magnetic energy density behaves like an additional pressure that adds to the gas pressure of a plasma.

In normal (linear and nondispersive) substances, the energy density (in SI units) is

u={\frac {1}{2}}(\mathbf {E} \cdot \mathbf {D} +\mathbf {H} \cdot \mathbf {B} )

where D is the electric displacement field and H is the magnetizing field.

In the case of absence of magnetic fields, by exploiting Fröhlich's relationships it is also possible to extend these equations to anisotropic and nonlineardielectrics, as well as to calculate the correlated Helmholtz free energy and entropy densities.^[85]

When a pulsed laser impacts a surface, the radiant exposure, i.e. the energy deposited per unit of surface, may be called energy density or fluence.^[86]

See also[edit]

https://en.wikipedia.org/wiki/Energy_density

https://en.wikipedia.org/wiki/Pressure_gradient

https://en.wikipedia.org/wiki/Internal_energy

https://en.wikipedia.org/wiki/Thermodynamic_system

https://en.wikipedia.org/wiki/Potential_energy

https://en.wikipedia.org/wiki/Mass

https://en.wikipedia.org/wiki/Thermodynamics

https://en.wikipedia.org/wiki/Exergy

https://en.wikipedia.org/wiki/Energy

https://en.wikipedia.org/wiki/Stress–energy_tensor

https://en.wikipedia.org/wiki/Relative_atomic_mass

https://en.wikipedia.org/wiki/Atomic_mass

https://en.wikipedia.org/wiki/Gravimetry

https://en.wikipedia.org/wiki/calorie

https://en.wikipedia.org/wiki/bomb_calorimeter

https://en.wikipedia.org/wiki/joule

https://en.wikipedia.org/wiki/enthalpy

https://en.wikipedia.org/wiki/entropy

https://en.wikipedia.org/wiki/stochastics

https://en.wikipedia.org/wiki/static

https://en.wikipedia.org/wiki/dynamic

https://en.wikipedia.org/wiki/state

https://en.wikipedia.org/wiki/function

https://en.wikipedia.org/wiki/scalar

https://en.wikipedia.org/wiki/vector

https://en.wikipedia.org/wiki/magnitude

https://en.wikipedia.org/wiki/direction

https://en.wikipedia.org/wiki/vector_field

https://en.wikipedia.org/wiki/space

https://en.wikipedia.org/wiki/plane

https://en.wikipedia.org/wiki/vertical_pressure_variation

https://en.wikipedia.org/wiki/linear_motor

https://en.wikipedia.org/wiki/linear_induction_motor

https://en.wikipedia.org/wiki/spinor

https://en.wikipedia.org/wiki/spiral

https://en.wikipedia.org/wiki/angular_acceleration

https://en.wikipedia.org/wiki/velocity

https://en.wikipedia.org/wiki/drag

https://en.wikipedia.org/wiki/medium

https://en.wikipedia.org/wiki/mechanics

https://en.wikipedia.org/wiki/electromagnetism

https://en.wikipedia.org/wiki/chemical

https://en.wikipedia.org/wiki/physical

https://en.wikipedia.org/wiki/nuclear

https://en.wikipedia.org/wiki/biological

https://en.wikipedia.org/wiki/maths

https://en.wikipedia.org/wiki/materials

https://en.wikipedia.org/wiki/equipment

https://en.wikipedia.org/wiki/system

https://en.wikipedia.org/wiki/surroundings

https://en.wikipedia.org/wiki/nested_system

https://en.wikipedia.org/wiki/propellant

https://en.wikipedia.org/wiki/dessicant

https://en.wikipedia.org/wiki/hydrogen

https://en.wikipedia.org/wiki/hydrogen_emission_spectra

https://en.wikipedia.org/wiki/Hydrogen_spectral_series

https://en.wikipedia.org/wiki/absorption_spectroscopy

https://en.wikipedia.org/wiki/Emission_spectrum

https://en.wikipedia.org/wiki/Spectroscopy

https://en.wikipedia.org/wiki/oscillation

https://en.wikipedia.org/wiki/particle

https://en.wikipedia.org/wiki/dust

https://en.wikipedia.org/wiki/agglomerate

https://en.wikipedia.org/wiki/order

https://en.wikipedia.org/wiki/hierarchy

https://en.wikipedia.org/wiki/pattern

https://en.wikipedia.org/wiki/step

https://en.wikipedia.org/wiki/rule

https://en.wikipedia.org/wiki/set

https://en.wikipedia.org/wiki/Astronomical_spectroscopy

https://en.wikipedia.org/wiki/Astronomy

https://en.wikipedia.org/wiki/shear

https://en.wikipedia.org/wiki/mass

https://en.wikipedia.org/wiki/efficiency

Pressure (symbol: p or P) is the force applied perpendicular to the surface of an object per unit area over which that force is distributed.^: 445^[1] Gauge pressure (also spelled gage pressure)^[a] is the pressure relative to the ambient pressure.

Various units are used to express pressure. Some of these derive from a unit of force divided by a unit of area; the SI unit of pressure, the pascal (Pa), for example, is one newton per square metre (N/m²); similarly, the pound-force per square inch (psi) is the traditional unit of pressure in the imperial and U.S. customarysystems. Pressure may also be expressed in terms of standard atmospheric pressure; the atmosphere (atm) is equal to this pressure, and the torr is defined as 1⁄760 of this. Manometric units such as the centimetre of water, millimetre of mercury, and inch of mercury are used to express pressures in terms of the height of column of a particular fluid in a manometer.

Pressure
Common symbols	p, P
SI unit	Pascal [Pa]
In SI base units	1 N/m², 1 kg/(m·s²), or 1 J/m³
Derivations from other quantities	p = F / A
Dimension	M L⁻¹ T⁻²

https://en.wikipedia.org/wiki/Pressure

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