A 10-ohm electric heater is connected to a 220V, 50Hz main supply. What is the peak value of the potential differences across the heater element:
Correct answer: D. (220 times sqrt{2})
- A. 220V
- B. (frac{220}{sqrt{2}})
- C. 110V
- D. (220 times sqrt{2})
Explanation
In an AC circuit, the peak voltage ((V_{{peak}})) is related to the RMS voltage ((V_{{rms}})) by the formula:[ V_{{peak}} = V_{{rms}} times sqrt{2} ]Given that the RMS voltage is 220V, the peak voltage is:[ V_{{peak}} = 220 times sqrt{2} ]Explanations for Wrong Choices:- (a) 220V: Incorrect. This would be the RMS value, not the peak value.- (b) (frac{220}{sqrt{2}}): Incorrect. This would be the RMS value, not the peak value.- (c) 110V: Incorrect. This is half of the RMS value, not the peak value.So, the correct answer is (d) (220 times sqrt{2}).
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