An alternating current varies as I = 4 sin(200πt). The frequency of the current is.
Correct answer: A. 100 Hz
- A. 100 Hz
- B. 200 Hz
- C. 400 Hz
- D. 800 Hz
Explanation
The general form for a sinusoidal current is I = I_peak sin(ωt), where ω is the angular frequency. By comparing this to the given equation, we see that ω = 200π. The relationship between angular frequency and linear frequency (f) is ω = 2πf, so f = ω / 2π = 200π / 2π = 100 Hz.
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About Alternating Current
Alternating current varies periodically, so phase relationships become essential when current passes through a resistor, capacitor or inductor. The chapter distinguishes resistance from capacitive and inductive reactance, explains phase lead and lag, and connects changing electric and magnetic fields with the production and properties of electromagnetic waves.
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