A condenser of capacity C is charged to a potential difference

A condenser of capacity C is charged to a potential difference of V1. The plates of the condenser are
then connected to an ideal inductor of inductance L. The current through the inductor when the potential difference across the condenser reduces to V₂ is

1. [C(V₁² - V₂²)/L]^1/2
2. [C(V₁ - V₂)²/L]^1/2
3. [C(V₁² - V₂²)/L]
4. [CV₁ - V₂)/L]

q = CV₁ cos wt

⇒ i =	dq	= - ω Cv₁ sin ωt
	dt

Also, ω² =	1	and V = V₁ cos ωt
	LC

At t = t₁, V = V₂ and i = -ω CV₁ sinωt₁

∴ cos ωt₁ =	V₂	(–ve sign gives direction)
	V₁

= {C(V₁²) - V₂²) / L}²