A capacitor of capacitance C has charge Q and stored energy is W. lf the charge is increase to 2Q. The stored energy will be:
Correct answer: D. 4W
- A. W/4
- B. W/2
- C. 2W
- D. 4W
Explanation
We know that the energy stored in a capacitor is given by: W=Q2 /2C Now, if the charge Q increases to 2Q, then the change in energy will be given by: W′=(2Q)2 /2C ⇒4Q2/2C =4W THUS THIS IS THE CORRECT ANSWER.
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