A charged capacitor stores 10 C at 40 V.. Its stored energy is:
Correct answer: D. 200 J
- A. 400 J
- B. 4 J
- C. 0.2 J
- D. 200 J
Explanation
The energy stored in a capacitor can be calculated using the formula U = 0.5 * Q * V, where U is the energy, Q is the charge, and V is the voltage. Given Q = 10 C and V = 40 V, the calculation is U = 0.5 * 10 C * 40 V = 200 J. Therefore, the correct answer is 200 J. The other options (400 J, 4 J, and 0.2 J) are incorrect because they do not follow the correct application of the formula.
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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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