MCQ
Two parallel plates have equal and opposite charge. When the space between them is evacuated, the electric field between the plates is $2 \times {10^5}\,V/m$. When the space is filled with dielectric, the electric field becomes $1 \times {10^5}\,V/m$. The dielectric constant of the dielectric material
  • A
    $1/2$
  • B
    $1$
  • $2$
  • D
    $3$

Answer

Correct option: C.
$2$
c
(c) $K = \frac{{{E_{{\rm{without \,dielectric }}}}}}{{{E_{{\rm{with\, dielectric}}}}}} = \frac{{2 \times {{10}^5}}}{{1 \times {{10}^5}}} = 2$

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