In an AC circuit shown below in figure, the supply voltage has a constant rms value V but variable frequency f. At resonance, the circuit

has a current given by $\mathrm{I}=\frac{\mathrm{V}}{\sqrt{{\mathrm{R}}^2+{\left(\frac{1}{\mathrm{\pi }}+\frac{1}{\mathrm{\pi }}\right)}^2}}$

has a voltage across the capacitor which is 180^o out of phase with that across the inductor

has current l given by $\mathrm{I}=\frac{\mathrm{V}}{\mathrm{R}}$

has a resonance frequency 500 Hz