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How many time constants will elapse before the current in a charging RC circuit drops to half of its initial value?

Text Solution

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`Q/2 = Q (1- e^(-t/rc))`
` 1/2 = (1 - e^(-t/rc))`
` e^(-t/rc) = 1/2`
` t/rC = log2 ` rArr n = 0.69.`
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HC VERMA-ELECTRIC CURRENT IN CONDUCTORS-Exercises
  1. The plates of a capacitor of capacitance 10(mu)F,charged to 60(mu)C,ar...

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  2. A capacitor of capacitance 8.0(mu)F is connected to a bettery of emf 6...

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  3. A parallel-plate capacitor of plate area 40 cm^2 and separation betwee...

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  4. A parallel-plalte capacitor has plate area 20cm^(2),plate separation 1...

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  5. A 100(mu)F capacitor is joined to a 24 V battery through a 1.0 M(Omega...

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  6. How many time constants will elapse before the current in a charging R...

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  7. How many time constants will elapse before the charge on a capacitor f...

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  8. How many time constants will elapse before the energy stored in the ca...

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  9. how many time constants will elapse before the power delovered by the ...

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  10. A capacitor of capacitance C is connected to a battery of emf (epsilon...

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  11. A capacitor of capacitance 12(mu)Fis connected to a battery of emf 6.0...

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  12. A capacitance C charged to a potential difference V is discharged by c...

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  13. By evaluating int i^(2)Rdt,show that when a capacitor is charged by co...

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  14. A parallel-plate capacitor is filled with a delectric meterial having ...

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  15. Find the charge on each of the capacitor 0.20ms after the switch S is ...

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  16. The switch S shown in figure is kept closed for a long time and is the...

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  17. A capacitor of capacitance 100(mu)F is connected across a battery of e...

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  18. Consider the situation shown in figure.The switch is closed at t=0when...

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  19. A capacitor of capacitance as C is given a charge Q. At t=0,it is conn...

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  20. A capacitor of capacitance as C is given a charge Q. At t=0,it is conn...

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