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A simple pendulum of length $L$ is placed between the plates of a parallel plate capacitor having electric field $E,$ as shown in figure. Its bob has mass $m$ and charge $q.$ the time period of the pendulum is given by
  • A$2\pi \sqrt {\frac{L}{{\sqrt {{g^2}\, - \,\frac{{{q^2}{E^2}}}{{{m^2}}}} }}} $
  • B$2\pi \sqrt {\frac{L}{{\left( {g\, + \,\frac{{qE}}{m}} \right)}}} $
  • C$2\pi \sqrt {\frac{L}{{\left( {g\, - \,\frac{{qE}}{m}} \right)}}} $
  • D$2\pi \sqrt {\frac{L}{{\sqrt {{g^2}\, + \,{{\left( {\frac{{qE}}{m}} \right)}^2}} }}} $
JEE MAIN 2019, Diffcult
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