Tuning an LC Circuit to Span 540 kHz Range

AI Thread Summary
The discussion centers on tuning an LC circuit in a radio receiver to span a frequency range of 540 kHz, with an inductance of 11.00 μH. The participant attempts to calculate the required capacitance using the formula C = 1/(ω²L), where ω is the angular frequency. However, the error arises from confusing frequency with angular frequency, as ω should be calculated using ω = 2πf. The correct capacitance calculation should use the angular frequency, leading to a different value than initially computed. Understanding the distinction between frequency and angular frequency is crucial for accurate calculations in LC circuits.
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Homework Statement



A radio receiver contains an LC circuit whose natural frequency of oscillation can be adjusted, or tuned, to match the frequency of the incoming radio waves. The adjustment is made by means of a variable capacitor. Suppose that the inductance of the circuit is 11.00 μH. What capacitance must the capacitor be adjusted to if the circuit is to span the 540.00 kHz range?

Homework Equations



\omega = \sqrt{L/C}

The Attempt at a Solution



\omega = \sqrt{L/C}
\omega = 540.00 kHz
L = 11.00 microH
C = what we're looking for

I solved for C getting C = \frac{1}{\omega^2 L}
C = \frac{1}{(540000Hz)^2 * .000011 H}
C = \frac{1}{3.20E6}
C = 3.1176E-7 F

Where am I going wrong?
 
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C = 1/3207600
 
You are mixing up frequency with angular frequency. Remember that

\omega=2\pi f
 
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