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Current Electricity — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsCurrent Electricity2 Marks
Question
If a constant potential difference is applied across a bulb, the current slightly decreases as time passes and then becomes constant. Explain.
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Answer

As current passes through wire of bulb it heats up and thus the resistance of wire (element) increase as its metal so current decreases as resistance increases after element is heated well the resistance stops increasing thus current stops decreases.

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