A parallel plate capacitor with air (εr = 1) has capacitance C. If a dielectric with εr = 3 is inserted, the new capacitance is:
Correct answer: C. 3C
- A. C/3
- B. C
- C. 3C
- D. 2C
Explanation
Capacitance is C = ε₀εrA/d. With a dielectric of εr = 3, the capacitance becomes 3C, as εr increases the permittivity.
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Electrostatics describes forces between charges through Coulomb's law, electric fields and field intensity, then uses electric potential to measure energy per unit charge. Capacitors store charge and electrical energy, with capacitance depending on geometry and dielectric material, not simply on the amount of charge present.
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