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Ch 32: AC Circuits
Knight Calc - Physics for Scientists and Engineers 5th Edition
Knight Calc5th EditionPhysics for Scientists and EngineersISBN: 9780137344796Non è quello che usi tu?Cambia libro di testo
Capitolo 32, Problema 19b

What are VR and VC if the emf frequency in FIGURE EX32.19 is 25 kHz?

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Identify the components of the circuit in FIGURE EX32.19. Typically, this type of problem involves a resistor (R), a capacitor (C), and an inductor (L) in an AC circuit. The voltage across the resistor (Vᵣ) and the capacitor (Vc) need to be determined at a given frequency.
Recall the formulas for the voltage across the resistor and capacitor in an AC circuit. The voltage across the resistor is given by: Vr = I R, where I is the current and R is the resistance. The voltage across the capacitor is given by: Vc = I Xc, where Xc = 1 / (2 π f C) is the capacitive reactance.
Determine the capacitive reactance Xc using the formula: Xc = 1 / (2 π f C). Substitute the given frequency (f = 25 kHz) and the capacitance (C) from the circuit diagram into the formula.
Calculate the current (I) in the circuit. Use Ohm's law for AC circuits: I = \(\text{emf}\) / Z, where Z is the total impedance of the circuit. The impedance Z can be calculated using the formula: Z = \(\text{sqrt}\)(R^2 + (XL - XC)^2), where XL = 2 π f L is the inductive reactance.
Finally, substitute the values of I, R, and Xc into the formulas for Vr and Vc to determine the voltages across the resistor and capacitor, respectively.

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