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2 years ago

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A capacitor is charged to a potential difference of 12v it delivers 40% of its stored energy to a lamp what is the final potenti

al difference across the capacitor

1 answer:

Korolek [52]2 years ago

6 0

Call the capacitance C.
<span>Note the energy in a capacitor with voltage V is E =½CV². </span>

<span>Initial energy = ½C(12)² = 72C </span>

<span>40% of energy is delivered, so 60% remains.in the capacitor. </span>
<span>Remaining energy = (60/100) x 72C =43.2C </span>

<span>If the final potential difference is X, the energy stored is ½CX² </span>
<span>½CX² = 43.2C </span>
<span>X² = 2 x 43.2 = 86.4 </span>
<span>X = 9.3V</span>

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3 years ago

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2 years ago