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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 8a

The peak current to and from a capacitor is 10 mA. What is the peak current if the emf frequency is doubled?

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1
Understand the relationship between the current through a capacitor and the frequency of the applied emf. The current through a capacitor is given by the formula: I = C ω V, where I is the current, C is the capacitance, ω is the angular frequency, and V is the peak voltage.
Recall that the angular frequency ω is related to the frequency f by the equation: ω = 2πf. Doubling the frequency f will also double the angular frequency ω.
Since the current I is directly proportional to the angular frequency ω, doubling the frequency will result in the current also being doubled.
The initial peak current is given as 10 mA. Therefore, if the frequency is doubled, the new peak current will be twice the initial peak current.
Conclude that the new peak current can be calculated as Inew = 2 × 10 mA. Perform this multiplication to find the final value if needed.

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