CapacitanceHard
Question
A resistor ′R′ and 2μF capacitor in series is connected through a switch to 200 V direct supply. Across the capacitor is a neon bulb that lights up at 120 V. Calculate the value of R to make the bulb light up 5 s after the switch has been closed. (log10 2.5 = 0.4)
Options
A.1.7 × 105 Ω
B.2.7 × 106 Ω
C.3.3 × 107 Ω
D.1.3 × 104 Ω
Solution
Vc = E( 1 - e- t/Rc)
1 - e- t/Rc =
2.7 × 106 Ω
1 - e- t/Rc =
2.7 × 106 ΩCreate a free account to view solution
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