Question:
Which of the following statements is not true for electric energy in ac form compared to that in dc form?
Which of the following statements is not true for electric energy in ac form compared to that in dc form?
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AC peak voltage is \(\sqrt{2} \times V_{rms}\). For a 220V supply, the peak is actually 311V, which is one reason why it's more hazardous than 220V DC.
Updated On: Feb 22, 2026
- Production of ac is economical.
- ac can be easily and efficiently converted from one voltage to the other.
- ac can be transmitted economically over long distances.
- ac is less dangerous.
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The Correct Option is D
Solution and Explanation
Step 1: Understanding the Concept:
Alternating Current (AC) and Direct Current (DC) have different physical properties and industrial advantages. This question asks to identify a \textit{false} statement about AC.
Step 2: Detailed Explanation:
1. Statement A: True. AC generators are simpler and more robust than DC generators. 2. Statement B: True. Transformers allow us to step-up or step-down AC voltage with very high efficiency. 3. Statement C: True. Because we can step-up AC to very high voltages, we can transmit it at low current, reducing \(I^2R\) heat losses. 4. Statement D: False. AC is generally considered \textit{more} dangerous than DC of the same voltage. AC of 220V has a peak value of about 311V. Furthermore, AC frequencies (50-60Hz) are particularly disruptive to the human heart's rhythm.
Step 3: Final Answer:
The statement "ac is less dangerous" is not true.
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