Consider two idealized systems: $(i)$ a parallel plate capacitor with large plates and small separation,and $(ii)$ a long solenoid of length $L \gg R$,where $R$ is the radius of the cross-section. In $(i)$,$E$ is ideally treated as a constant between the plates and zero outside. In $(ii)$,the magnetic field is constant inside the solenoid and zero outside. These idealized assumptions,however,contradict fundamental laws as follows:

  • A
    Case $(i)$ contradicts Gauss's law for electrostatic fields.
  • B
    Case $(ii)$ contradicts Gauss's law for magnetic fields.
  • C
    Case $(i)$ agrees with $\oint E \cdot dl = 0$.
  • D
    Case $(ii)$ contradicts $\oint H \cdot dl = I_{en}$.

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