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A coil of self inductance 10 mH and resistance 0.1 Ω is connected through a switch to a battery of internal resistance 0.9 Ω . After the switch is closed, the time taken for the current to attain 80% of the saturation value is: [take l n 5 = 1.6]

1. 0.324 s
2. 0.002 s
3. 0.103 s
4. 0.016 s

Correct answer: 0.016 s

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