Chapter 24: Alternating Current Circuits Selected Solutions

Selected Solutions

31. The rms current is given by I_rms = V_rms/Z, where . Therefore,

41. The impedance is given by . Therefore,

47. The inductive reactance can be found from the impedance,

The impedance is given by . Therefore,

55. (a) Since the resonance frequency is inversely proportional to the square root of the product of L and C, the resonance frequency will decrease if L and C are doubled.

(b)

65. (a) Recall that , where X is the reactance of the inductor or the capacitor. If X increases, I_rms decreases. If X decreases, I_rms increases.

So, the box must contain a capacitor.

(b) The capacitance can be found from capacitive reactance which part of the impedance,

Since C cannot be negatice we only take the positive square root for the result. Given that Z can be determined from Z = V_rms/I_rms, we have

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