Two square air-filled parallel plates that are initially uncharged are separated by 1.2 mm,and each of them has an area of 190 mm².How much charge must be transferred from one plate to the other if 1.1 nJ of energy are to be stored in the plates? (ε₀₀ = 8.85 × 10^-12 C²/N ∙ m²) A)56 pC B)39 pC C)78 pC D)3.5 µC

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Quizplus · Accepted Answer

The energy stored in a capacitor is given by $ U = \frac{Q^2}{2C} $. The capacitance $ C $ of parallel plates is $ C = \frac{\varepsilon_0 A}{d} $. Solving for $ Q $ using $ U = 1.1 \times 10^{-9} $ J, $ A = 190 \times 10^{-6} $ m$^2$, and $ d = 1.2 \times 10^{-3} $ m gives $ Q \approx 56 $ pC.

Two Square Air-Filled Parallel Plates That Are Initially Uncharged Are