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What current flows when a 60.0 Hz, 480 V AC source is connected to a 0.250 μF capacitor?

a) 2.08 A
b) 3.12 A
c) 4.16 A
d) 5.20 A

User Nick Chubb
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1 Answer

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Final answer:

The current that flows through a 0.250 µF capacitor when connected to a 60 Hz, 480 V AC source is approximately 45.3 mA, which does not match any of the given multiple-choice options. At 25.0 kHz, the current would be approximately 7.53 A.

Step-by-step explanation:

The current that flows when a 60.0 Hz, 480 V AC source is connected to a 0.250 µF capacitor can be calculated using the formula for capacitive reactance (XC) and then using Ohm's law to find the current (I). The capacitive reactance is given by XC = 1 / (2πfC), where f is the frequency in hertz and C is the capacitance in farads. To find the current (I), use the formula I = V / XC, where V is the voltage in volts.

First, calculate the reactance for a frequency (f) of 60 Hz:

XC = 1 / (2π × 60 × 0.250 × 10-6) = 1 / (2π × 60 × 0.250 × 10-6) ≈ 1 / (0.000015) ≈ 10,600 Ω

Now, calculate the current I using the RMS voltage (Vrms) of 480 V:

I = Vrms / XC = 480 / 10600 ≈ 0.0453 A or 45.3 mA, which is not listed in the multiple-choice options provided.

For part (b) of your question, at a frequency of 25.0 kHz, the reactance would be:

XC = 1 / (2π × 25,000 × 0.250 × 10-6) ≈ 1 / (0.0157) ≈ 63.7 Ω

And the current I would be:

I = Vrms / XC = 480 / 63.7 ≈ 7.53 A

User Matt Long
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