# Oscillating Charged Disc!

A massless point charge $$Q_1 = -125 \ \mu C$$ is fixed at the center of an insulated disc of mass $$1kg$$. The disc rests on a rough horizontal plane. Another massless charge $$Q_2 = 125 \ \mu C$$ is fixed above the center of the disc at a height $$h=1$$ m. The disc is displaced slightly in the horizontal direction and begins to oscillate harmonically, find the period of oscillation $$T$$ (in seconds) of the disc's oscillation.

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