What is Current: Definition and 1000 Discussions

An electric current is a stream of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is measured as the net rate of flow of electric charge through a surface or into a control volume. The moving particles are called charge carriers, which may be one of several types of particles, depending on the conductor. In electric circuits the charge carriers are often electrons moving through a wire. In semiconductors they can be electrons or holes. In a electrolyte the charge carriers are ions, while in plasma, an ionized gas, they are ions and electrons.The SI unit of electric current is the ampere, or amp, which is the flow of electric charge across a surface at the rate of one coulomb per second. The ampere (symbol: A) is an SI base unit Electric current is measured using a device called an ammeter.Electric currents create magnetic fields, which are used in motors, generators, inductors, and transformers. In ordinary conductors, they cause Joule heating, which creates light in incandescent light bulbs. Time-varying currents emit electromagnetic waves, which are used in telecommunications to broadcast information.

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  1. Tesladude

    Magnetic field put off by high current (causing cross-talk between wires)

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  2. R

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  3. T

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  4. M

    Magnetic Field due to Opposing Coils

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  5. M

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  6. F

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  7. Perodamh

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  8. J

    RMS or Average Current Homework - Tips & Tricks

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  9. Dave Johnson

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  10. M

    What is the Direction of Induced Current?

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  11. D

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  12. D

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  13. srinaath

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  14. H

    What's the current from this circuit? Is it a short circuit or not?

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  15. T

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  16. duhuhu

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  17. Abdullah Almosalami

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  18. binbagsss

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  19. T

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  20. F

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  21. F

    What type of energy does electrical current have?

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  23. L

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  24. J

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  25. Altair Tans

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  26. J

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  27. J

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  29. P

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  31. H

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  32. W

    Proof of Wheatstone bridge equation

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  33. Pushoam

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  34. F

    Current flowing from point A in a circuit to point B

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  35. SW Dad

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  36. K

    Diagram about potential difference over current

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  37. G

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  38. H

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  39. B

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  40. PhiowPhi

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  41. H

    Find the current I in this electrical circuit

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  42. T

    Current Density between two infinite plates

    Hi, I'm studying the "Child Langmuir law". We have a grounded cathode that is an infinite plane with free electrons, and an anode with a positive voltage V. The text says that the current density J is constant between the two plates for the "Charge conservation principle". I was not able to...
  43. Steven Robinson

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  44. M

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  45. Vivek098

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  46. J

    Current Angle More Than Ninety Degrees

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  47. J

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  48. lekh2003

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  49. Y

    Wouldn't using AC to power a lamp result in flickering?

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  50. VSayantan

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