Why Does the Current Halve at This Frequency in an AC Series Circuit?

AI Thread Summary
In an AC series circuit with a resistor and an inductor, the frequency at which the current is half its value at zero frequency can be calculated using the formula f=sqrt(3R)/(2*pi*L). The given values are R = 12 ohms and L = 4.5 mH. An initial calculation yielded a frequency of 212.21 Hz, which was identified as incorrect. The discussion highlights the need to verify the frequency formula used in the calculation. Accurate understanding of the relationship between resistance, inductance, and frequency is crucial for solving such problems.
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Homework Statement



A series circuit contains only a resistor and an inductor. The voltage V of the generator is fixed. If R = 12 ohms and L = 4.5 mH, find the frequency at which the current is one-half its value at zero frequency. Note: The ac current and voltage are rms values and power is an average value unless indicated otherwise.


Homework Equations



f=sqrt(3R)/2*pi*L


The Attempt at a Solution



I calculated 212.21 Hz but this was incorrect

 
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Your equation for the frequency is wrong. How did you get it? ehild
 

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