NEET2017PhysicsAlternating CurrentActual
In an L C R circuit as shown in figure, both switches are open initially. Now switch S₁ is closed, S₂ kept open. ( q is charge on the capacitor and =R C is capacitive time constant). Which of the following statement is correct?
Options
- AAt t= 2 , q=C V (1-e⁻¹ )
- BWork done by the battery is half of the energy dissipated in the resistor
- CAt t= , q=C V / 2
- DAt t=2 , q=C V (1-e⁻² )
Correct answer
D. At t=2 , q=C V (1-e⁻² )
Step-by-step solution
As switch S₁ is closed and switch S₂ is kept open. Now, capacitor is charging through a resistor R . Charge on a capacitor at any time t is q=q₀ (1-e^ -t / )=C V (1-e^ -t / ) aligned & At t= 2 , q=C V (1-e^ - / 2 )=C V (1-e^ -1 / 2 ) & At t= , q=C V (1-e^ - / )=C V (1-e⁻¹ ) & At t=2 , q=C V (1-e^ -2 / )=C V (1-e⁻² ) aligned