# Joule's Experiment: an Historico-Critical Approach

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• Magnetic Fields Magnetism Magnetic Field
PHY2061 Enriched Physics 2 Lecture Notes Magnetic Fields Magnetic Fields Disclaimer: These lecture notes are not meant to replace the course textbook. The content may be incomplete. Some topics may be unclear. These notes are only meant to be a study aid and a supplement to your own notes. Please report any inaccuracies to the professor. Magnetism Is ubiquitous in every-day life! • Refrigerator magnets (who could live without them?) • Coils that deflect the electron beam in a CRT television or monitor • Cassette tape storage (audio or digital) • Computer disk drive storage • Electromagnet for Magnetic Resonant Imaging (MRI) Magnetic Field Magnets contain two poles: “north” and “south”. The force between like-poles repels (north-north, south-south), while opposite poles attract (north-south). This is reminiscent of the electric force between two charged objects (which can have positive or negative charge). Recall that the electric field was invoked to explain the “action at a distance” effect of the electric force, and was defined by: F E = qel where qel is electric charge of a positive test charge and F is the force acting on it. We might be tempted to define the same for the magnetic field, and write: F B = qmag where qmag is the “magnetic charge” of a positive test charge and F is the force acting on it. However, such a single magnetic charge, a “magnetic monopole,” has never been observed experimentally! You cannot break a bar magnet in half to get just a north pole or a south pole. As far as we know, no such single magnetic charges exist in the universe, D.
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• 3-D Electromagnetic Radiative Non-Newtonian Nanofluid Flow With
www.nature.com/scientificreports OPEN 3‑D electromagnetic radiative non‑Newtonian nanofuid fow with Joule heating and higher‑order reactions in porous materials Amel A. Alaidrous1* & Mohamed R. Eid2,3* The aim of this work is to discuss the efect of mth‑order reactions on the magnetic fow of hyperbolic tangent nanofuid through extending surface in a porous material with thermal radiation, several slips, Joule heating, and viscous dissipation. In order to convert non‑linear partial diferential governing equations into ordinary ones, a technique of similarity transformations has been implemented and then solved using the OHAM (optimal homotopy analytical method). The outcomes of novel efective parameters on the non‑dimensional interesting physical quantities are established utilizing the tabular and pictorial outlines. After a comparison with previous literature studies, the results were fnely compliant. The study explores that the reduced Nusselt number is diminished for the escalating values of radiation, porosity, and source (sink) parameters. It is found that the order of the chemical reaction m = 2 is dominant in concentration as well as mass transfer in both destructive and generative reactions. When m reinforces for a destructive reaction, mass transfer is reduced with 34.7% and is stabled after η = 3. In the being of the destructive reaction and Joule heating, the nanofuid’s temperature is enhanced. Abbreviations a, b Constants (–) B0 Magnetic parameter C Concentration (mol/m3) cp Specifc heat C Free stream concentration (mol/m3)
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• 3.Joule's Experiments
The Force of Gravity Creates Energy: The “Work” of James Prescott Joule http://www.bookrags.com/biography/james-prescott-joule-wsd/ James Prescott Joule (1818-1889) was the son of a successful British brewer. He tinkered with the tools of his father’s trade (particularly thermometers), and despite never earning an undergraduate degree, he was able to answer two rather simple questions: 1. Why is the temperature of the water at the bottom of a waterfall higher than the temperature at the top? 2. Why does an electrical current flowing through a conductor raise the temperature of water? In order to adequately investigate these questions on our own, we need to first define “temperature” and “energy.” Second, we should determine how the measurement of temperature can relate to “heat” (as energy). Third, we need to find relationships that might exist between temperature and “mechanical” energy and also between temperature and “electrical” energy. Definitions: Before continuing, please write down what you know about temperature and energy below. If you require more space, use the back. Temperature: Energy: We have used the concept of gravity to show how acceleration of freely falling objects is related mathematically to distance, time, and speed. We have also used the relationship between net force applied through a distance to define “work” in the Harvard Step Test. Now, through the work of Joule, we can equate the concepts of “work” and “energy”: Energy is the capacity of a physical system to do work. Potential energy is “stored” energy, kinetic energy is “moving” energy. One type of potential energy is that induced by the gravitational force between two objects held at a distance (there are other types of potential energy, including electrical, magnetic, chemical, nuclear, etc).
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• Electric Permittivity of Carbon Fiber
Carbon 143 (2019) 475e480 Contents lists available at ScienceDirect Carbon journal homepage: www.elsevier.com/locate/carbon Electric permittivity of carbon ﬁber * Asma A. Eddib, D.D.L. Chung Composite Materials Research Laboratory, Department of Mechanical and Aerospace Engineering, University at Buffalo, The State University of New York, Buffalo, NY, 14260-4400, USA article info abstract Article history: The electric permittivity is a fundamental material property that affects electrical, electromagnetic and Received 19 July 2018 electrochemical applications. This work provides the ﬁrst determination of the permittivity of contin- Received in revised form uous carbon ﬁbers. The measurement is conducted along the ﬁber axis by capacitance measurement at 25 October 2018 2 kHz using an LCR meter, with a dielectric ﬁlm between specimen and electrode (necessary because an Accepted 11 November 2018 LCR meter is not designed to measure the capacitance of an electrical conductor), and with decoupling of Available online 19 November 2018 the contributions of the specimen volume and specimen-electrode interface to the measured capaci- tance. The relative permittivity is 4960 ± 662 and 3960 ± 450 for Thornel P-100 (more graphitic) and Thornel P-25 ﬁbers (less graphitic), respectively. These values are high compared to those of discon- tinuous carbons, such as reduced graphite oxide (relative permittivity 1130), but are low compared to those of steels, which are more conductive than carbon ﬁbers. The high permittivity of carbon ﬁbers compared to discontinuous carbons is attributed to the continuity of the ﬁbers and the consequent substantial distance that the electrons can move during polarization. The P-100/P-25 permittivity ratio is 1.3, whereas the P-100/P-25 conductivity ratio is 67.
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• Joule Heating of the South Polar Terrain on Enceladus K
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 116, E04010, doi:10.1029/2010JE003776, 2011 Joule heating of the south polar terrain on Enceladus K. P. Hand,1 K. K. Khurana,2 and C. F. Chyba3 Received 12 November 2010; revised 1 February 2011; accepted 13 February 2011; published 27 April 2011. [1] We report that Joule heating in Enceladus, resulting from the interaction of Enceladus with Saturn’s magnetic field, may account for 150 kW to 52 MW of power through Enceladus. Electric currents passing through subsurface channels of low salinity and just a few kilometers in depth could supply a source of power to the south polar terrain, providing a small but previously unaccounted for contribution to the observed heat flux and plume activity. Studies of the electrical heating of Jupiter’s moon Europa have concluded that electricity is a negligible heating source since no connection between the conductive subsurface and Alfvén currents has been observed. Here we show that, contrary to results for the Jupiter system, electrical heating may be a source of internal energy for Enceladus, contributing to localized heating, production of water vapor, and the persistence of the “tiger stripes.” This contribution is of order 0.001–0.25% of the total observed heat flux, and thus, Joule heating cannot explain the total south polar terrain heat anomaly. The exclusion of salt ions during refreezing serves to enhance volumetric Joule heating and could extend the lifetime of liquid water fractures in the south polar terrain. Citation: Hand, K. P., K. K. Khurana, and C. F. Chyba (2011), Joule heating of the south polar terrain on Enceladus, J.
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• Work and Energy Summary Sheet Chapter 6
Work and Energy Summary Sheet Chapter 6 Work: work is done when a force is applied to a mass through a displacement or W=Fd. The force and the displacement must be parallel to one another in order for work to be done. F (N) W =(Fcosθ)d F If the force is not parallel to The area of a force vs. the displacement, then the displacement graph + W component of the force that represents the work θ d (m) is parallel must be found. done by the varying - W d force. Signs and Units for Work Work is a scalar but it can be positive or negative. Units of Work F d W = + (Ex: pitcher throwing ball) 1 N•m = 1 J (Joule) F d W = - (Ex. catcher catching ball) Note: N = kg m/s2 • Work – Energy Principle Hooke’s Law x The work done on an object is equal to its change F = kx in kinetic energy. F F is the applied force. 2 2 x W = ΔEk = ½ mvf – ½ mvi x is the change in length. k is the spring constant. F Energy Defined Units Energy is the ability to do work. Same as work: 1 N•m = 1 J (Joule) Kinetic Energy Potential Energy Potential energy is stored energy due to a system’s shape, position, or Kinetic energy is the energy of state. motion. If a mass has velocity, Gravitational PE Elastic (Spring) PE then it has KE 2 Mass with height Stretch/compress elastic material Ek = ½ mv 2 EG = mgh EE = ½ kx To measure the change in KE Change in E use: G Change in ES 2 2 2 2 ΔEk = ½ mvf – ½ mvi ΔEG = mghf – mghi ΔEE = ½ kxf – ½ kxi Conservation of Energy “The total energy is neither increased nor decreased in any process.
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• Measuring Electricity Voltage Current Voltage Current
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• The Avogadro Constant to Be Equal to Exactly 6.02214X×10 23 When It Is Expressed in the Unit Mol −1
[august, 2011] redefinition of the mole and the new system of units zoltan mester It is as easy to count atomies as to resolve the propositions of a lover.. As You Like It William Shakespeare 1564-1616 Argentina, Austria-Hungary, Belgium, Brazil, Denmark, France, German Empire, Italy, Peru, Portugal, Russia, Spain, Sweden and Norway, Switzerland, Ottoman Empire, United States and Venezuela 1875 -May 20 1875, BIPM, CGPM and the CIPM was established, and a three- dimensional mechanical unit system was setup with the base units metre, kilogram, and second. -1901 Giorgi showed that it is possible to combine the mechanical units of this metre–kilogram–second system with the practical electric units to form a single coherent four-dimensional system -In 1921 Consultative Committee for Electricity (CCE, now CCEM) -by the 7th CGPM in 1927. The CCE to proposed, in 1939, the adoption of a four-dimensional system based on the metre, kilogram, second, and ampere, the MKSA system, a proposal approved by the ClPM in 1946. -In 1954, the 10th CGPM, the introduction of the ampere, the kelvin and the candela as base units -in 1960, 11th CGPM gave the name International System of Units, with the abbreviation SI. -in 1970, the 14 th CGMP introduced mole as a unit of amount of substance to the SI 1960 Dalton publishes first set of atomic weights and symbols in 1805 . John Dalton(1766-1844) Dalton publishes first set of atomic weights and symbols in 1805 . John Dalton(1766-1844) Much improved atomic weight estimates, oxygen = 100 . Jöns Jacob Berzelius (1779–1848) Further improved atomic weight estimates .
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• Active Short Circuit - Chassis Short Characterization and Potential Mitigation Technique for the MMRTG
Jet Propulsion Laboratory California Institute of Technology Multi-Mission RTG Active Short Circuit - Chassis Short Characterization and Potential Mitigation Technique for the MMRTG February 25, 2015 Gary Bolotin1 Nicholas Keyawa1 1Jet Propulsion Laboratory, California Institute of Technology 1 Jet Propulsion Laboratory California Institute of Technology Agenda Multi-Mission RTG • Introduction – MMRTG – Internal MMRTG Chassis Shorts • Active Short Circuit Purpose • Active Short Circuit Theory • Active Short Design and Component Layout • Conclusion and Future Work 2 Jet Propulsion Laboratory California Institute of Technology Introduction – MMRTG Multi-Mission RTG • The Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) utilizes a combination of PbTe, PbSnTe, and TAGS thermoelectric couples to produce electric current from the heat generated by the radioactive decay of plutonium – 238. 3 Jet Propulsion Laboratory Introduction – Internal MMRTG Chassis California Institute of Technology Shorts Multi-Mission RTG • Shorts inside the MMRTG between the electrical power circuit and the MMRTG chassis have been detected via isolation checks and/or changes in the bus balance voltage. • Example location of short shown below MMRTG Chassis Internal MMRTG Short 4 Jet Propulsion Laboratory California Institute of Technology Active Short Circuit Purpose Multi-Mission RTG • The leading hypothesis suggests that the FOD which is causing the internal shorts are extremely small pieces of material that could potentially melt and/or sublimate away given a sufficient amount of current. • By inducing a controlled second short (in the presence of an internal MMRTG chassis short), a significant amount of current flow can be generated to achieve three main design goals: 1) Measure and characterize the MMRTG internal short to chassis, 2) Safely determine if the MMRTG internal short can be cleared in the presence of another controlled short 3) Quantify the amount of energy required to clear the MMRTG internal short.
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• Chapter 7 Magnetism and Electromagnetism
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• Chapter 22 Magnetism
Chapter 22 Magnetism 22.1 The Magnetic Field 22.2 The Magnetic Force on Moving Charges 22.3 The Motion of Charged particles in a Magnetic Field 22.4 The Magnetic Force Exerted on a Current- Carrying Wire 22.5 Loops of Current and Magnetic Torque 22.6 Electric Current, Magnetic Fields, and Ampere’s Law Magnetism – Is this a new force? Bar magnets (compass needle) align themselves in a north-south direction. Poles: Unlike poles attract, like poles repel Magnet has NO effect on an electroscope and is not influenced by gravity Magnets attract only some objects (iron, nickel etc) No magnets ever repel non magnets Magnets have no effect on things like copper or brass Cut a bar magnet-you get two smaller magnets (no magnetic monopoles) Earth is like a huge bar magnet Figure 22–1 The force between two bar magnets (a) Opposite poles attract each other. (b) The force between like poles is repulsive. Figure 22–2 Magnets always have two poles When a bar magnet is broken in half two new poles appear. Each half has both a north pole and a south pole, just like any other bar magnet. Figure 22–4 Magnetic field lines for a bar magnet The field lines are closely spaced near the poles, where the magnetic field B is most intense. In addition, the lines form closed loops that leave at the north pole of the magnet and enter at the south pole. Magnetic Field Lines If a compass is placed in a magnetic field the needle lines up with the field.
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• Page 1 of 29 Dalton Transactions