Energy stored in the electric field of a capacitor C when charged from a D.C source of voltage V is equal to joules
Correct answer: A. 0.5 CV2
- A. 0.5 CV2
- B. CV2
- C. 0.5C2V
- D. 0.5CV
Explanation
The correct answer is Option A: 0.5 CV2. The energy stored in a capacitor when it is charged is given by the formula E = 0.5CV2. This formula accounts for the voltage squared and includes a factor of 0.5 that arises from integration of the charge over the potential difference. Option B (CV2) is incorrect as it omits the factor of 0.5, Option C (0.5C2V) incorrectly squares the capacitance instead of the voltage, and Option D (0.5CV) fails to square the voltage.
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About Electrostatics
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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