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Ask your administrator if you think this is wrong. ====== Energy ====== This section as for goal to present different energy conversion and examples[(https://en.wikipedia.org/wiki/Energy)]. ===== Some forms of energy ===== <WRAP group> <WRAP half column> In every use: * Mechanical: the sum of macroscopic translational and rotational kinetic and potential energies * Gravitational: potential energy due to or stored in gravitational fields * Chemical: potential energy due to chemical bonds * Elastic: potential energy due to the deformation of a material (or its container) exhibiting a restorative force * Sound wave: kinetic and potential energy in a fluid due to a sound propagated wave (a particular form of mechanical wave) * Radiant: potential energy stored in the fields of propagated by electromagnetic radiation, including light * Thermal: kinetic energy of the microscopic motion of particles, a form of disordered equivalent of mechanical energy </WRAP> <WRAP half column> Microscopic energy: * Mechanical wave: kinetic and potential energy in an elastic material due to a propagated deformational wave * Electric: potential energy due to or stored in electric fields * Magnetic: potential energy due to or stored in magnetic fields * Ionization: potential energy that binds an electron to its atom or molecule * Nuclear: potential energy that binds nucleons to form the atomic nucleus (and nuclear reactions) * Chromodynamic: potential energy that binds quarks to form hadrons * Rest: potential energy due to an object's rest mass </WRAP> </WRAP> ===== Energy unity conversion ===== * 1 J = 1 m.N = 1 W.s * 1 W.h = 3.6 kJ * 1 cal = 4.184 J * 1 hp.s = 750 J (one horsepower for 1s) ---- ===== Scale of energy in 'every day' use ===== <WRAP group> <WRAP half column> * 10 fJ = energy deliverer to a the eardrum by listening one second to a whisper * 1 dJ = energy of a leaf falling one meter on earth * 1 J = kinetic energy produced as an extra small apple (~100 grams) falls 1 meter against Earth's gravity * 1 J = energy required to heat 1 gram of dry, cool air by 1 degree Celsius * 4.184 J = energy needed to raise the temperature of one gram of water by one degree Celsius * 300 J = one person jumping as high as the can (70kg, 40cm on eath) * 330 J = melting 1g or ice * 360 J = Kinetic energy of 800 gram standard men's javelin thrown at > 30 m/s by elite javelin throwers * 1.4 kJ = average energy receive from the sun in 1m²/s * 2.3 kJ = vaporizing 1g of water into steam * 3.1 kJ = Kinetic energy of world-record men's hammer throw (7.26 kg thrown at 30.7 m/s in 1986) * 4.2 kJ = energy release by 1g of TNT * 9 kJ = 1 AA baterry * 17 kJ = 1g of carbohydrates or protein * 38 kJ = 1g of fat * 50 kJ = 1g of matter at 10km/s * 600 kJ = 1 automobile (2t) at 90 km/h * 1.2 MJ = energy of a snack such as a snickers bar (280 kcal) * 5.2 MJ = average heat lost by a human in a day * 8.4 MJ = Recommended food energy intake per day for a moderately active woman (2000 food calories) * 11 MJ = Recommended food energy intake per day for a moderately active man (2600 food calories) * 40 MJ = Energy from the combustion of 1 cubic meter of natural gas * 42 MJ = Caloric energy consumed by Olympian Michael Phelps on a daily basis during Olympic training * 110 MJ ≈ 1 Tour de France, or ~90 hours ridden at 5 W/kg by a 65 kg rider * 1-10 GJ = Energy in an average lightning bolt * 1.4 GJ = Theoretical minimum amount of energy required to melt a tonne of steel * 2 GJ = Energy of an ordinary 61 liter gasoline tank of a car * 3.3 GJ = Approximate average amount of energy expended by a human heart muscle over an 80-year lifetime * 4.5 GJ = Average annual energy usage of a standard refrigerator </WRAP> <WRAP half column> * 19 GJ = Kinetic energy of an Airbus A380 at cruising speed (560 tonnes at 511 knots or 263 m/s) * 88 GJ = Total energy released in the nuclear fission of one gram of uranium-235 * 240 GJ = Approximate food energy consumed by an average human in an 80-year lifetime (2000 kcal for 80 years) * 11 TJ = Energy of the maximum fuel an Airbus A380 can carry (320,000 liters of Jet A-1) * 12 TJ = Orbital kinetic energy of the International Space Station * 63 TJ = Yield of the Little Boy atomic bomb dropped on Hiroshima in World War II (15 kilotons) * 90 TJ = Theoretical total mass-energy of 1 gram of matter * 600 TJ = Energy released by an average hurricane in 1 second * 100 PJ = Energy released on the Earth's surface by the magnitude 9.1–9.3 2004 Indian Ocean earthquake * 170 PJ = Total energy from the Sun that strikes the face of the Earth each second * 210 PJ = Yield of the Tsar Bomba, the largest nuclear weapon ever tested (50 megatons) * 420 PJ = Yearly electricity consumption of Norway as of 2008 * 800 PJ = Estimated energy released by the eruption of the Indonesian volcano, Krakatoa, in 1883 * 5 EJ = Energy released in 1 day by an average hurricane in producing rain (400 times greater than the wind energy) * 64 EJ = Yearly electricity consumption of the world as of 2008 * 500 EJ = Total world annual energy consumption in 2010 * 800 EJ = Estimated global uranium resources for generating electricity 2005 * 7.9 ZJ = Estimated energy contained in the world's petroleum reserves as of 2010 * 39 ZJ = Estimated energy contained in the world's fossil fuel reserves as of 2010 * 500 ZJ = Approximate energy released in the formation of the Chicxulub[(https://en.wikipedia.org/wiki/Chicxulub_crater)] Crater in the Yucatán Peninsula * 5.5 YJ = Total energy from the Sun that strikes the face of the Earth each year * 380 YJ = Total energy output of the Sun each second * 38k YJ = Kinetic energy of the Moon in its orbit around the Earth (counting only its velocity relative to the Earth) * 2.1M YJ = Rotational energy of the Earth * 4.2 10e45 YJ = Estimated total mass-energy of the observable universe </WRAP> </WRAP> ---- ===== Examples ===== ==== Sound ==== The energy of the sound is given by the equation: E = time (s) * area (m²) * intensity (W/m²) or E = time (s) * area (m²) * 10e(-12+db/10). For a person (1m²) absorbing the sound during one second: * 20 db = whisper = 0.1 nJ * 60 db = normal conversation = 1 µJ * 98 db = Large Orchestra = 6.3 mJ * 130 db = pain threshold = 10 J === Gravitational === The potential energy due to the gravitational field: E = mass (kg) * g (=10 m/s²) * deltaZ (m) Examples for lifting one object of 1m: * 1 dJ = a leaf * 1 J = a small apple * 800 J = one person Levitation would need to generate a velocity of 9.8m/s each second. E = 1/2 m v² = 50J/kg. P = 50W/kg. The energy necessary to levitate for one minute for a standard person of 75kg would be 225kJ. === Kinetic === Kinetic energy due to velocity: E = 1/2 * mass (kg) * velocity² (m/s) * 0.5 J = 1kg at 1m/s === Food === Energy release by the metabolism: * 17 kJ = 1g of carbohydrates or protein * 38 kJ = 1g of fat * 1.2 MJ = energy of a snack such as a snickers bar (280 kcal) * 8.4 MJ = Recommended food energy intake per day for a moderately active woman (2000 food calories) * 11 MJ = Recommended food energy intake per day for a moderately active man (2600 food calories) === Combustion === Chemical energy: * 40 MJ = Energy from the combustion of 1 cubic meter of natural gas * 730 MJ ≈ Energy from burning 16 kilograms of oil * 2 GJ = Energy of an ordinary 61 liter gasoline tank of a car == Can I launch a Fireball ?== Let hypothesis that we don't want a combustible but just a source of heat and light. For a candlelight: light : 1 candela in all direction = 13 lumens = 2cW/s = 2cJ/s heat: 80 W = 80 J/s ---- ==== What does a person can do ? ==== === Just with the every day food === A person eat between 1500 kcal and 3000 kcal = 6-12 MJ, lets take 10 MJ * boiling 4l of water from room temperature 20°C * lift a canon ball (20kg) up to 50km or throwing it at 1km/s * lift a car (2t) up to 500m or trowning it at 100m/s === Using their body reserve === 1 kg muscle (protein) = 17 MJ, 1 kg fat = 38 MJ, 1 Kg water at 37°C = 4.2 kJ/°C <WRAP group> <WRAP third column> Skinny person 50kg = 15kg muscle + 3kg fat + 2kg bones + 30kg water Reserve energy = 15kg muscle + 3kg fat = 255 MJ + 114 MJ = 369 MJ Water heat energy = 126 KJ/°C </WRAP> <WRAP third column> Athlete 80kg = 40kg muscle + 8kg fat + 2kg bone + 30kg water Reserve energy = 40kg muscle + 8kg fat = 680 MJ + 304 MJ = 948 MJ Water heat energy = 126 KJ/°C </WRAP> <WRAP third column> Fat person 100kg = 28kg muscle + 30kg fat + 2kg bone + 40kg water Reserve energy = 28kg muscle + 30kg fat = 476 MJ + 1.1 GJ = 1,6 GJ Water heat energy = 168 KJ/°C </WRAP> </WRAP> ---- ==== SI multiples ==== <WRAP group> <WRAP half column> * 10e−1 J-dJ-decijoule * 10e−2 J-cJ-centijoule * 10e−3 J-mJ-millijoule * 10e−6 J-µJ-microjoule * 10e−9 J-nJ-nanojoule * 10e−12 J-pJ-picojoule * 10e−15 J-fJ-femtojoule * 10e−18 J-aJ-attojoule * 10e−21 J-zJ-zeptojoule * 10e−24 J-yJ-yoctojoule </WRAP> <WRAP half column> * 10e1 J-daJ-decajoule * 10e2 J-hJ-hectojoule * 10e3 J-kJ-kilojoule * 10e6 J-MJ-megajoule * 10e9 J-GJ-gigajoule * 10e12 J-TJ-terajoule * 10e15 J-PJ-petajoule * 10e18 J-EJ-exajoule * 10e21 J-ZJ-zettajoule * 10e24 J-YJ-yottajoule </WRAP> </WRAP> start/miscellaneous/energy.txt Last modified: 2023/11/06 14:11by aretis