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Home , Energy transformation, Kilogram, Potential energy, Pound (force), Slug (unit)

Science of of Science    Traditional FormsEnergy of Thermal EnergyThermal Energy Kinetic Energy

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metin /~    Energy generation is actually from one form to another to form one from transformation energy actually is generation Energy Formsof Energy: Science: of law Fundamental – – – – – – – – Boiling water rises: Thermal Thermal rises: water Boiling Kinetic hands: Rubbing Dropping a pen:: Electric and Electromagnetic Magnetic Kinetic and Energy:Potential, Traditional Thermal to energy energy Wasting is an form actually transforming undesirable if even energy you want. waste You cannot - Based Energy: Chemical and Nuclear and : Based Forms of Energy of Forms → → Thermal Kinetic Kinetic → Potential Energy and are conserved. are mass and Energy

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metin /~    Comparison between metric and imperialand metric between Comparison Potential Energy Gravitational forceWeight= – – – – – Imperial Imperial Metric 1 kg Ex: What Gravitationalinforce Ex: What Then Mass in Potential Energy » » = It It The gravitational ? Would your answer change if the person takes an an takes person if the change answer your ? Would per per meters kg square 80(9.8)10 is 0.068 s (kg); constant constant (kg); Acceleration kilogram weight kilogram is 784=80(9.8) is the potential energy gained by a by gained energy is potential the mass? kilogram 80 withperson a of to) applying forceweight(gravitationalis the Mass s Kilogram = Roughly Roughly = Mass Mass mass 2.20 force Potential Energy Potential kg m lbm Slug:Kilogram:Pound lbm = in in ∗ . 14.65 kg . Gravitational force Newton Newton Gravitationalacceleration constant g GravitationalAcceleration g 32.20 Feet per ( * second) * second) (second per Feet 32.20 1.00 Feet per (second * second) * second) (second per Feet 1.00 9.81 & Heightin meters = squaresecond or meters meters kg x m/ kg = 1 s per (second * second) m/ * second) (second per per per = person person s in in 32.2 square second second square 2 force ratios are32 2 : 1. : metres ⇒ mg simply simply lbm with 80 kg mass walking walking kg mass 80 with P otential energy in . 0.45 kg. x Height h x Height per square second (m/ second square per 7,840 7,840 elevator? elevator? or 784 or . joule. ft ft newtons = / / s s s 2 2 0.031 slug 2 Pound force lbf Pound force lbf N Newton Force . J oule s stairs up for 10 2 = = ) Newton x Newton 1 lbm .

If you never hear of slug metre

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& wonder where it is used, Page

metin check crossword puzzles. /~        passing through the propeller? propeller? the through after down passing slows flow air the when does much how is lost energy propeller), the to (no is passed perfect is energy kinetic flow's conversion air energy the that Assuming it. rotate to propeller the right the at propeller Consider Ex: drop? the of bottom An Ex: themass to is proportional energyKinetic bottom the at energy kinetic becomes energy potential Furthermore, have must We Initial 0 mass of object an Drop – – The The is which lost, By Hence energy Kinetic Potential Energy accounting book weighs 1 kg and is dropped from 1 1 from dropped is and 1 kg weighs book accounting using the , we can say the gained is equal to the potential energy energy potential the to equal is gained energy kinetic the say we can energy, of conservation the using kinetic energy of of kinetic energy each airincoming is particle , air particles lose half of their speed after transferring their energy to energy to their of half transferring lose speed after , their air particles a horizontalcylinder which is subject to air flow from left to right. Thereis a ℎ & = mgh final speedat the bottom 𝑚𝑚 = Distance 2 𝑣𝑣 hand side of the cylinder. The air flow passes passes flow air The cylinder. the of side -hand 𝑖𝑖 2 =1(9.8)1=9.8 =1(9.8)1=9.8 = − 2 1 𝑚𝑚 = Kinetic Energy 4 3 𝑚𝑚 from a height of of height a from 𝑚𝑚 𝑚𝑚 𝑣𝑣 2 𝑣𝑣 2 𝑖𝑖 Average speed Average 2 , where where , ℎ = = joule. 2 1 𝑚𝑚 𝑚𝑚 𝑣𝑣 𝑣𝑣 2 𝑖𝑖 𝑔𝑔𝑔𝑔 is the speed the is 2 2 & 𝑔𝑔 ℎ = 𝑇𝑇 , which takes time takes which , ∗ square of the speed from above. In general, In above. from speed the of square , average speed average, 2 1 Time = 𝑚𝑚 2 1 𝑚𝑚 𝑣𝑣 2 𝑚𝑚 𝑜𝑜 𝑣𝑣 2 = 𝑖𝑖 2 at the entry and and entry the at at at 𝑔𝑔 𝑔𝑔𝑔𝑔 the exit for for exitthe 2 2 𝑇𝑇 = , metre 𝑔𝑔 Kinetic energy Kinetic 𝑇𝑇 / 2 𝑣𝑣 what is its kineticenergy at the 𝑜𝑜 75% = 𝑣𝑣 2 𝑖𝑖 of its kinetic energy to to energy itsof kinetic the the . propeller .

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metin /~          how much is needed? needed? is energy thermal much how this amount of energy? of amount this 80 a with with kg can climb mass meters person salads. manyHow 1000 sells Ex: A cafeteria 1 calorie= 4.2 joule & as such capacity high salts. with and molten water substances needs the industry of energy, transportation and storage For of (330 0.33 Ex: the Totemperature increase kilogram energy thermal absorb to a substance of ability the is constant capacity Heat is in 0 measured ; is kelvin Sometimes x (kilogram per joule in is constant capacity Heat Massis in kilogram Thermal Energy – – – – No! Dieticians use calorie to mean kilocalories. The salad actually has 1,000,000 which can be burnt by 5350 by of burnt be can mountain building which a a of calories climbing 1,000,000 has actually floors The salad two kilocalories. mean to climb calorie to use Dieticians No! sufficient it is salad, a burn To of 80 energy is the = which 4200 joule, potential 1000 calorie 0.33(4200)50=69,300 is water for needed energy The Thermal Energy = For water 4200 joule per (kilogram x increases the temperature of 1 water by 1 Celsius 1 by water gram 1 of temperature the increases Thermal Energy metres Mass Mass ! 𝑚𝑚 ∗ constant Heat capacity constant celsius ) > For sand 835 millilitre ) or ) or . − kg person at 5.35 5.35 at person kg 273 ?? ol e klga x (kilogram per joule , can soda ) of water by 50 by of 50 can, soda water size) celsius joule per (kilogram x celsius (kilogram per joule 𝐶𝐶 metres ∗ Temperature = kelvin) kelvin) 4,200/(80 4,200/(80 * ). ). 9.8 celsius 𝐾𝐾 )

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metin /~ Summary    Thermal EnergyThermal Energy Kinetic Potential Energy

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metin /~          Linguistic Insight: Words “Pound” & “Ponder” are relatives. are “Ponder” & “Pound” Words Insight:Linguistic isLibra shortened lb.as P Libra Litra (Skal Funt inPond Pfund EmpireFrench British – – – But these are all shortened as as all shortened are But these use: in pounds many but one, only Not mass. of unit the as pound used British )Pund in in in Byzantine Empirein » » » » » » » » in in E ondo Russian Empire Which Empirehad Imperial Units? the Netherlands the Livre Livre de Paris Livre Livre Avoir Pound Troy Pound Tower Pound Merchant Pound London mpire Prussian Empire in in ( of weighing)in(weights - du metrique esterin Swedish Empire - pois (goods Ponderis - of A lot of them! ofA lot → - weight in French) Pound French) inweight lb , why? , : To weigh in Latin. in : To weigh for volumenow Roman Empire . . H andle andle for suspension Museo Cup Bronze B with with A Livre Litre Litra Archeologico chain with with chain hook l Libra youthful youthful b alance, Naples alance, Pondo head of Nazionale Pfund Pound Pund Pond Funt , .

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metin /~