When 4 volts e.m.f is applied across of I frad capacitor, It will store energy of:
Correct answer: D. 8 joules
- A. 2 joules
- B. 6 joules
- C. 4 joules
- D. 8 joules
Explanation
The energy stored in a capacitor is given by the formula E = 0.5 * C * V^2, where E is the energy in joules, C is the capacitance in farads, and V is the voltage in volts. For a 1 farad capacitor with 4 volts applied: E = 0.5 * 1 * (4)^2 = 0.5 * 16 = 8 joules. Hence, the correct answer is 8 joules. Options A, B, and C are incorrect as they do not align with the computed result from the formula.
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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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