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प्रश्न
Find the potential difference required to flow a current of 300 mA in a wire of resistance 20 Ω.
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उत्तर
Potential difference V = ?
Current I = 300 mA = 0.2 A,
R = 20 Ω
V = IR
V = `3/10 xx 20`
= 6 V
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