What is Electricity and magnetism: Definition and 214 Discussions

Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles. The electromagnetic force is carried by electromagnetic fields composed of electric fields and magnetic fields, and it is responsible for electromagnetic radiation such as light. It is one of the four fundamental interactions (commonly called forces) in nature, together with the strong interaction, the weak interaction, and gravitation. At high energy, the weak force and electromagnetic force are unified as a single electroweak force.

Electromagnetic phenomena are defined in terms of the electromagnetic force, sometimes called the Lorentz force, which includes both electricity and magnetism as different manifestations of the same phenomenon. The electromagnetic force plays a major role in determining the internal properties of most objects encountered in daily life. The electromagnetic attraction between atomic nuclei and their orbital electrons holds atoms together. Electromagnetic forces are responsible for the chemical bonds between atoms which create molecules, and intermolecular forces. The electromagnetic force governs all chemical processes, which arise from interactions between the electrons of neighboring atoms. Electromagnetism is very widely used in modern technology, and electromagnetic theory is the basis of electric power engineering and electronics including digital technology.
There are numerous mathematical descriptions of the electromagnetic field. Most prominently, Maxwell's equations describe how electric and magnetic fields are generated and altered by each other and by charges and currents.
The theoretical implications of electromagnetism, particularly the establishment of the speed of light based on properties of the "medium" of propagation (permeability and permittivity), led to the development of special relativity by Albert Einstein in 1905.

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  1. T

    A few questions on electricity and magnetism and EM fields

    Hello: Many many years ago I walked away from community college with an associates degree in physics, and despite my fondness for the subject, I had to put it aside for other things. I recently happened upon something that lead me to realize how much I had forgotten, and so I've decided to...
  2. C

    Solve Basic Electricity and Magnetism Questions - No Calculations Needed

    Yes, yes I know about the template, but these questions are so basic that I don't really know what I can show as work... Sometimes all I need for help is the relevant equation itself -.- So please don't delete or hate. Thanks! 2. http://tinyimage.net/images/50136173150204648365.png The...
  3. A

    Electricity and Magnetism homework

    Homework Statement What is the Kinetic Energy of an electron that passes undeviated through perpendicular electric and magnetic fields if E = 4.0 kV/m and B = 8.0 mT? m_{e} = 9.1 \times 10^{-31} \textup{kg} q_{e} = 1.6 \times 10^{-19} \textup{C} Homework Equations I got stuck doing...
  4. A

    Is E&M a Significant Part of a MechE Degree?

    How much E&M is involved in a MechE degree? I'm a high school senior in AP Physics C: E&M and I hate it with a passion. I loved Mechanics, but E&M is terrible. Would I just need to take the one required class (Physics 2), or do I need to use multiple E&M concepts throughout undergrad? I am...
  5. S

    Problems about Electricity and Magnetism

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  6. C

    Electricity and Magnetism Question

    Homework Statement The potential caused by an array of charges in a region of space can be described by the equation V(x,y,z)=2x+xy+y2-xz2 volts, where all distances are measured in metres. If a charge of 2 mC is moved from the position r1=(1,2,0)m to r2=(3,1,0), calculate the resulting change...
  7. I

    Purcell - Electricity and Magnetism

    Does anyone know where I can purchase the hardcover 1985 Electricity and Magnetism? Some schools, such as Caltech and MIT, still use the book; however, Caltech does not have it in their online bookstore and MIT lists an 09 edition (which I assume is an ebook?). Some copies are floating...
  8. N

    Electricity and magnetism book (preferably with lots of examples)

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  9. K

    Do i need mechanics to learn electricity and magnetism?

    ? I'm just curious. Also I'm having trouble with mechanics. I feel like i have no idea how to grasp fnet and calculating it. I also REALLY REALLY REALLY suck at drawing free body diagram. Math is a walk compared to physics which feels like a marathon. I'm actually not that great with math but...
  10. Y

    Need a website that explains general physics 2 (electricity and magnetism)

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  11. A

    Understand concepts of electricity and magnetism

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  12. E

    How Does Charging a Ball Affect Its Pendulum Motion?

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  13. A

    My Answer: Explanation of Solutions for Electricity and Magnetism Problems

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  14. P

    Electricity and Magnetism Book

    I'm a first year undergraduate taking my first electricity and magnetism class, and going through all the classic material: Coulomb's law, electric fields, flux, capacitors, etc. And the book I have explains the material relatively well, but I feel like I'm missing out on so much by just being...
  15. B

    Help.Mayday.about electricity and magnetism

  16. D

    Dynamic, Electricity and Magnetism, Gravitational Force, Light etc.

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  17. D

    Mastering Physics: Tips for Success in Electricity and Magnetism

    I sincerely intend for this not to be a rant, please do not take it in this way. Well, the first half of my physics B AP class is over. We are all done with mechanics (/happyface) and now we are going to start part 2: Electricity and Magnetism. Mechanics was very hard for me. Why? I have no...
  18. B

    Maxwell's A Treatise on Electricity and Magnetism

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  19. J

    Electricity and magnetism HELP

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  20. M

    Electricity and Magnetism (Charged Plates)

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  21. T

    EE Assignment Electricity and magnetism

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  22. D

    Electricity and magnetism field lines

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  23. T

    Are Electricity and Magnetism Related or Inverses of Each Other?

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  24. A

    Question about electricity and magnetism

    Why is it that 2 wires carrying parallel current attract each other i think they should repeal imagine 2 wires carrying electrons to the left then the current is to the right, in the reference frame of the moving electrons it seems like the electrons on the other wire are not moving so the...
  25. P

    Electricity and Magnetism Question (Capacitor). .

    Okay, I will be honest, this is a homework assignment. For that matter this is the last homework assignment which is very crucial to preparing for the final. But the problem is I have 2 more finals for which I need to study for. So if you can please help me out and give a detailed solution I...
  26. P

    Electricity and Magnetism. (Mag Field)

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  27. P

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  28. P

    Electricity and Magnetism Question (Related to circuits). .

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  29. C

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  30. P

    Relationship between electricity and magnetism

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  31. D

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  32. M

    Electricity and Magnetism questions Gauss's law, groundingetc.

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  33. E

    Transition from mechanics to electricity and magnetism.

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  34. T

    Electricity and magnetism - planar symmetry question: plastic sheets

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  35. B

    Noob questions about electricity and magnetism

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  36. J

    Average Potential Electricity and Magnetism

    Homework Statement Find the average potential over a spherical surface of radius R due to a point charge q located inside. Show that in general: (EQ 1 below), where Vcenter is the potential at the center due to all external charges and Qenc is the total enclosed charge Homework Equations...
  37. H

    Electricity and Magnetism question.

    Hello I have these two questions on electricity and magnetism which I don't understand very well these are: (Q1) If a closed surface encloses no charge, and electric field lines cross the surface. (Q2) Under what conditions can coloumb's law be used to find the electric field strength...
  38. G

    Electricity and Magnetism on lines of charge

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  39. A

    Purcell's Electricity and Magnetism - question

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  40. T

    Electricity and Magnetism- Energy sources and power stations

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  41. A

    How are electricity and magnetism related?

    I know that electric fields generate magnetic fields (when you put a compass next to a wire that has current in it the needle moves indicating that a mag. field is present). I know that changing magnetic fields can generate electric fields or induced emf. What does electromagnetic waves...
  42. H

    The link between electricity and magnetism

    Hey everyone, I have a few questions. What is the link between electricity and magnetism? Why would moving electrons(current) create a magnetic field? Why does a moving magnetic field induce a current in a conductor? Thanks for responces.
  43. A

    Electricity and Magnetism Question

    I have a couple of questions in E&M. a)Can anyone tell me what a coaxial resistor and a coaxial capacitor looks like? (Approx Diagram) Because I am not sure which equations apply to them since I am not sure what they look like. b)How do I find a self energy of a charged sphere? Split it into...
  44. F

    What is the Tension in a Conducting Wire Connecting Two Charged Spheres?

    Homework Statement Two identical conducting spheres each having a radius of .5 cm are connected by a light 2.3 m long conducting wire. A charge of 53 uC is placed on one of the conductors. Assume that the surface distribution of charge on each sphere is uniform. Determine the tension in the...
  45. T

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    Homework Statement Five point charges on a straight line are separated by a distance of 0.01 m. For what values of q2 and q4 would the net force on each of the other three charges be zero? q1-----q2-----q3-----q4-----q5 Where: q1= 2x10^-6 C q3= 1x10^-6 C q5= 2x10^-6 C Homework...
  46. M

    Electricity and Magnetism Comics

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  47. M

    Electricity and Magnetism in a veloctiy selector

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  48. B

    Electricity and magnetism. 2 questions

    A couple of questions. 1. A capacitor of capacitance C is discharging through a resistor of resistance R. When will the energy stored be equal to half its initial value? My logic went like this: Energy in a capacitor (U) = Q^2/2C so: Q = (2CU)^0.5 so therefore the charge when the...
  49. M

    Electricity and Magnetism question

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  50. Astronuc

    What Does the Physics 122 Course by Frank L. Wolfs Cover?

    Physics 122 Course by Frank L. Wolfs (homepage - http://teacher.nsrl.rochester.edu/) Department of Physics and Astronomy University of Rochester http://teacher.nsrl.rochester.edu/phy122/Phy122HomePage.html#info Course notes [see post #4 for revised link]
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