What is the resonant frequency of a parallel RLC circuit if R is 4.7 kilohms, L is 5 microhenrys and C is 9 picofarads?

The resonant frequency of a tuned circuit, whether series or parallel, is determined by the formula f = 1 / (2π√(LC)). The value of the parallel resistor (R) affects the circuit's Q factor and bandwidth but does not change the resonant frequency, making it a distractor in this question. To solve, first convert the values to base units: L = 5 × 10^-6 henrys and C = 9 × 10^-12 farads. Multiply L and C to get 45 × 10^-18. Taking the square root gives approximately 6.708 × 10^-9. Finally, multiply this result by 2π (about 6.283) and divide 1 by that product. The result is roughly 23,720,000 hertz, which converts to 23.7 MHz. Distractor answers in kilohertz are commonly chosen if the student miscounts decimal places during conversion.