What will be the voltage across the capacitor at t = 0+

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What will be the voltage across the capacitor at t = 0⁺ for given figure?

1. 2 V
2. – 2 V
3. 4 V
4. 1 V

Correct Option: B

In order to find the voltage across capacitor at t = 0⁺ the circuit becomes

Note: In this type of question when both C and L are connected in the circuit, we can't apply general formula, because it is very difficult to calculate the time constant τ so we go for tricky method.
Apply KCL at node (1)

		V - 6	=	V - 0	+ 3 = 0
		4		2

		V	+	V	=	- 3
		4		2		2

or V = – 2 V.