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Electric Charges and Fields — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsElectric Charges and Fields1 Mark
MCQ
A closed surface S is constructed around a conducting wire connected to a battery and a switch (figure). As the switch is closed, the free electrons in the wire start moving along the wire. In any time interval, the number of electrons entering the closed surface S is equal to the number of electrons leaving it. On closing the switch, the flux of the electric field through the closed surface:

  • A
    Is increased.
  • B
    Is decreased.
  • C
    Remains unchanged.
  • D
    Remains zero.
✓

Answer

  1. Remains unchanged.

Explanation:

The flux of the electric field through the closed surface is remain unchanged.

Because the no. of electric field lines enter in the closed path = no. of electric field lines existsin the closed path.

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