The main power supply in India is at 220V, whereas that in the US is at 110 V. Which one among the following statements in this regard is correct?

The choice between 110V and 220V involves a trade-off between safety and efficiency. A 110V system is generally considered safer for residential use because lower voltage reduces the risk of severe electric shock and insulation breakdown. However, it is more expensive to maintain and install. According to the power formula (P = VI), for a given power requirement, a lower voltage (110V) necessitates a higher current. Higher current leads to increased resistive heating and power loss (I"R), requiring thicker copper wiring to handle the load and minimize energy waste. In contrast, 220V systems allow for thinner wires and lower transmission losses but carry a higher risk of lethal shock. Therefore, while 110V enhances personnel safety, the requirement for more conductor material (copper) and higher distribution losses makes it more costly to maintain.

Sources

1. [1] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 4: Electricity: Magnetic and Heating Effects > A step further > p. 54