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Magnetism And Matter — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMagnetism And Matter1 Mark
MCQ
When the current through the electromagnet of a relay reaches a particular value:
  • A
    It breaks the circuit.
  • B
    It open the circuit by pulling in an iron contact.
  • C
    It closes the circuit by pulling in an iron contact.
  • D
    Both A or C.
✓

Answer

  1. Both A or C.

Explanation:

They are ways of switching using a low current to use an electromagnet to close or open a spring steel contact.They are often used to isolate a user from a high voltage that needs to be switched, using low current, low voltage to operate the relay, rather than having a user come in direct proximity to the higher voltage that needs to be switched.When the current through the electromagnet of a relay reaches a particular value it either breaks the circuit by repllening or closes the circuit by pulling in an iron contact.

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