What is Switch: Definition and 562 Discussions

In electrical engineering, a switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electric current or diverting it from one conductor to another. The most common type of switch is an electromechanical device consisting of one or more sets of movable electrical contacts connected to external circuits. When a pair of contacts is touching current can pass between them, while when the contacts are separated no current can flow.
Switches are made in many different configurations; they may have multiple sets of contacts controlled by the same knob or actuator, and the contacts may operate simultaneously, sequentially, or alternately. A switch may be operated manually, for example, a light switch or a keyboard button, or may function as a sensing element to sense the position of a machine part, liquid level, pressure, or temperature, such as a thermostat. Many specialized forms exist, such as the toggle switch, rotary switch, mercury switch, push-button switch, reversing switch, relay, and circuit breaker. A common use is control of lighting, where multiple switches may be wired into one circuit to allow convenient control of light fixtures. Switches in high-powered circuits must have special construction to prevent destructive arcing when they are opened.

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  1. Eltahawy

    How quickly can an electric switch operate?

    Suppose a hypothetical experiment consisting of a lamp that is situated some where on the moon connected to a battery some where on Earth through an ideal conductor(with no losses at all) assume that we turned off the circuit at some time t0 how long it takes for the lamp to illuminate Or that...
  2. S

    Engineering Deciding to switch to mechanical engineering?

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  3. moenste

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  4. V

    A How to switch from tensor products to wedge product

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  5. seemasdawange

    Improving Transistor Switching for High Voltage Protection Circuits

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  6. S

    Find heat produced on closing the switch S

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  7. S

    Design 12:1 2.0 USB Multiplexer | Matija

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  8. P

    I Photonic crystal switch- directional couplers

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  10. G

    Engineering AC circuit with a switch -- analysis

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  12. marellasunny

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  13. D

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  14. Asylum

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  15. G

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  16. DevonZA

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  17. G

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  18. Planobilly

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  20. j3dwards

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  21. I

    The molecular switch from welcoming to attacking a pathogen?

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  22. G

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  23. S

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  24. S

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  27. P

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  28. 4

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  29. F

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  30. N

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  31. R

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  32. A

    Switch Types for Vehicle: 5 Pin & 2 Pin

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  33. A

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  34. K

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  35. J

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  36. G

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  37. A

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  38. R

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  39. T

    Best Ethernet / Network switch setup?

    My grandma recently gave me a relatively new Cisco gigabit ethernet / network switch because she never used it. Here are the devices that need to be wired: Here is the current setup: Internet / Wifi Modem upstairs, my bedroom / "tech studio" is in the downstairs / basement of the townhouse...
  40. AaronG1995

    How quickly does light turn on once you've hit the switch?

    Once you flipped the switch how quickly does the electricity reach the light bulb? I've read somewhere that it's at the speed of light but I might be wrong, I've also read somewhere that electrons flow very very slow so I can't understand how will lights will turn on instantly.
  41. M

    Engineering to Physics: Guidance for Undergraduate Students

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  42. neduet

    Double Busbar Scheme for outdoor switch yard system (132kv)

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  43. B

    How to wire up Piezo touch sensitive switch?

    Hi Everyone, I could do some advice on wiring up a Piezo touch sensitive switch. I'm in the middle of building a desk PC project and thought it would be a nice touch to have a touch sensitive power switch, so I've bought a nice shiny touch sensitive illuminated Piezo switch and can't figure out...
  44. I

    MATLAB Matlab Switch w/ string function

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  45. S

    Designing a Switch for XT90 Battery Connectors on Drones

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  46. J

    Engineering Finding Ix in Switch Circuit at Different Times

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  47. W

    Backup Camera with optional power source bypass switch

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  48. anorlunda

    Insights What Happens When You Flip the Light Switch? - Comments

    anorlunda submitted a new PF Insights post What Happens When You Flip the Light Switch? Continue reading the Original PF Insights Post.
  49. H

    How to set the frequency of a switch in NI Multisim software

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  50. A

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