Which of the following statement is true about RMS voltage?a)RMS volt...
- RMS voltage of a sinusoidal waveform is directly proportional to the peak voltage.
For a sinusoidal waveform,
- Multimeters measure average value of voltage and current of different waveforms.
- The RMS value of a sinusoidal waveform gives half of the heating effect than a DC current of the same value.
- The ratio of the RMS value of voltage to the maximum value of voltage is the same as the ratio of the RMS value of current to the maximum value of current.
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Which of the following statement is true about RMS voltage?a)RMS volt...
RMS Voltage
RMS voltage, also known as root mean square voltage, is a measure of the average voltage of an alternating current (AC) waveform. It is commonly used to represent the effective voltage of a sinusoidal waveform.
Explanation of the Correct Answer
The correct answer is option 'D': The ratio of the RMS value of voltage to the maximum value of voltage is the same as the ratio of the RMS value of current to the maximum value of current.
To understand why this statement is true, let's break it down into two parts: the ratio of RMS voltage to the maximum voltage, and the ratio of RMS current to the maximum current.
1. Ratio of RMS Voltage to Maximum Voltage:
- The maximum voltage, also known as peak voltage, is the highest value reached by an AC waveform.
- The RMS voltage is calculated by taking the square root of the average of the squares of all the instantaneous voltage values over one complete cycle of the waveform.
- For a sinusoidal waveform, the RMS voltage is equal to the peak voltage divided by the square root of 2 (√2).
- Mathematically, RMS voltage = (Peak voltage) / √2.
- Therefore, the ratio of RMS voltage to the maximum voltage is 1/√2 or approximately 0.707.
2. Ratio of RMS Current to Maximum Current:
- Similar to the voltage case, the maximum current is the highest value reached by an AC waveform.
- The RMS current is calculated using the same method as RMS voltage, but applied to the instantaneous current values instead.
- For a sinusoidal waveform, the RMS current is also equal to the peak current divided by the square root of 2 (√2).
- Mathematically, RMS current = (Peak current) / √2.
- Therefore, the ratio of RMS current to the maximum current is also 1/√2 or approximately 0.707.
Conclusion
The RMS value of voltage and current is calculated by dividing their respective peak values by the square root of 2. The ratio of the RMS value of voltage to the maximum value of voltage is the same as the ratio of the RMS value of current to the maximum value of current, which is approximately 0.707. This relationship holds true for sinusoidal waveforms, and it is an important concept in AC circuit analysis and calculations.
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