Question

220 V ac is more dangerous than 220 V d(C) Why?

• A. The peak value of ac is greater than the given value of dc
• B. Shock received from ac is always repulsive
• C. The frequency of ac is more than that of dc
• D. The speed of ac is more than that of dc

Hint:

When comparing ac and dc, remember that the RMS value of ac is the equivalent value in terms of energy dissipation, but the peak value is significantly higher, which increases the danger of electric shock.

Answer 1

The Correct Option is A

Alternating current (ac) and direct current (dc) are both forms of electric current, but they behave differently. In an ac circuit, the current alternates direction with time, whereas in a dc circuit, the current flows in only one direction. For a 220 V ac system, this value refers to the root mean square (RMS) value of the voltage, which is approximately the equivalent dc voltage in terms of energy dissipation. However, the peak value of ac is higher than the RMS value. The peak voltage \( V_{\text{peak}} \) of an ac signal is related to the RMS voltage \( V_{\text{RMS}} \) by the following equation: \[ V_{\text{peak}} = \sqrt{2} \times V_{\text{RMS}} = \sqrt{2} \times 220 \approx 311 \, \text{V} \] Thus, the peak value of ac is 311 V, which is higher than the 220 V given for d(C) This higher peak value is what makes ac more dangerous, as the maximum potential difference experienced in an ac system is greater than that in a corresponding dc system, leading to a greater risk of electric shock.