What is Elecricity: Definition and 97 Discussions

A third rail, also known as a live rail, electric rail or conductor rail, is a method of providing electric power to a railway locomotive or train, through a semi-continuous rigid conductor placed alongside or between the rails of a railway track. It is used typically in a mass transit or rapid transit system, which has alignments in its own corridors, fully or almost fully segregated from the outside environment. Third rail systems are always supplied from direct current electricity.
The third-rail system of electrification is not related to the third rail used in dual gauge railways.

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  1. B

    Capacitance of two spheres with equal radius

    I'm considering two identical spherical conductor each of radius ##a## and separated by a distance ##d##, and trying to figure out the capacitance of this configuration. My thoughts are that since capacitance is $$C=\frac {Q}{V}$$ and that the spherical conductors are equipotential surfaces...
  2. V

    Discussion about Altering Automotive Electricity Management

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  3. A

    Is Electromagnetic Braking Suitable for High-Speed Monorail Stopping?

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  4. bornofflame

    RC circuit - Rate o'energy dissipated = rate o'energy stored

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  5. Aishikdesto

    Nature of charge at the junction of a composite wire

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  6. Kevin J

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  7. F

    I Proof that the E field inside a cylindrical resistor is constant

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  8. Raihan amin

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  9. F

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  10. S

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  11. F

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  12. Nemika

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  13. F

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  14. F

    Electromagnetic Waves: Static Charges & Relativity Predictions

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  15. F

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  16. A

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  17. mheruian

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  18. C

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  19. F

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  20. S

    Engineering How hands-on is Electrical Engineering?

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  21. Cassius1n

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  22. N

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  23. P

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  24. N

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  25. A

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  26. S

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  27. B

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  28. lbwet

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  29. V

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  30. Helmy

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  31. Cheesycheese213

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  32. doglover9754

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  33. K

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  34. F

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  35. KoontzyN

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  36. D fatima

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  37. Sveral

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  38. SW Dad

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  39. B

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  40. Y

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  41. J

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  42. M

    Question regarding phase shift between two signals

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  43. PrincePhoenix

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  44. S

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  45. M

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  46. E

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  47. S

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