If the length, width, and separation between the plates of a parallel plate capacitor are doubled, then its capacitance becomes:
Correct answer: A. Double
- A. Double
- B. Half
- C. Four-times
- D. Eight-times
Explanation
The capacitance of a parallel plate capacitor is given by C = A/D Where ε is the permittivity of the dielectric, A is the area of the plates, and D is the distance between them. As D is in the denominator, capacitance is inversely proportional to the distance between plates, or separation. As A is in the numerator, it is directly proportional to C, where A = width x length. It then follows that if the length, width, and separation between the plates of a parallel plate capacitor are doubled, then its capacitance will also double.
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About Capacitors
Capacitors store electric charge and energy in an electric field between conductors. Work includes capacitance, the relation Q = CV, dielectric materials, charging and discharging, energy formulas, and combinations of capacitors in series and parallel. Electric potential difference is needed to understand why charge and stored energy change.
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