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Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsElectrostatic Potential and Capacitance1 Mark
MCQ
In a region of constant potential:
  • A
    The electric field is uniform.
  • B
    The electric field is zero.
  • C
    There can be no charge inside the region.
  • D
    The electric field shall necessarily change if a charge is placed outside the region.
✓

Answer

  1. The electric field is zero.
  2. There can be no charge inside the region.

We know, the electric field intensity E and electric potential V are dV related as $\text{E}=-\frac{\text{dV}}{\text{dr}}$

or we can write $|\text{E}|=-\frac{\Delta\text{V}}{\Delta\text{r}}$

The electric field intensity E and electric potential V are related as E = 0 and for V = constant, $\frac{\text{dV}}{\text{dr}}=0$ this imply that electric field intensity E = 0.

If some charge is present inside the region then electric field cannot be zero at that region, for this V = constant is not valid.

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