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A capacitor of capacitance C is initially charged and then allowed to discharge through a small coil of resistance R placed inside a thermally insulated block of mass m and specific heat capacity s. If the block’s temperature increases by ΔT, what was the potential difference V across the capacitor initially?

1. mCΔT / s
2. √(2mCΔT / s)
3. √(2msΔT / C)
4. msΔT / C

Correct answer: √(2msΔT / C)

Solution

The correct option is derived from the energy conservation principle, where the energy stored in the capacitor, given by (1/2)CV², is converted into heat energy absorbed by the block, which is calculated as msΔT. By equating these two forms of energy and solving for V, we find that V equals √(2msΔT / C).

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