An A.C voltmeter reads 250 volts. The frequency of alternating is 50 Hz, the peak value of voltage is:
Correct answer: C. 353.5 volts
- A. 3525.0 volts
- B. 35.35 volts
- C. 353.5 volts
- D. 3.535 volts
Explanation
The correct answer is 353.5 volts. The A.C. voltmeter reads the RMS (Root Mean Square) value of the voltage, which is 250 volts in this case. To find the peak voltage (Vpeak), we use the formula Vpeak = VRMS × √2. Thus, Vpeak = 250 × √2 ≈ 353.5 volts. This calculation shows why Option C is correct. Options A, B, and D are incorrect as they do not accurately apply this formula, leading to values that do not make sense in the context of RMS and peak relationships.
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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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