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

Options

A. 110 V is safer but more expensive to maintain
B. 110 V is safer and cheaper to maintain
C. 110 V leads to lower power loss
D. 110 V works better at higher latitudes

Explanation

To determine which statement is correct regarding the main power supply voltages in India (220 V) and the US (110 V), we will analyze the implications of these voltage levels on electrical appliances and safety.

### Step-by-Step Solution:

1. **Understanding Voltage Levels**:
- In India, the main power supply voltage is 220 V.
- In the US, the main power supply voltage is 110 V.

2. **Ohm's Law**:
- According to Ohm's Law, the relationship between voltage (V), current (I), and resistance (R) is given by the formula:
\[ V = I \cdot R \]
- This implies that for a given resistance, an increase in voltage will result in an increase in current.

3. **Current Calculation**:
- Let's assume the resistance (R) of an appliance is constant.
- For the Indian supply (220 V):
\[ I_{India} = \frac{V_{India}}{R} = \frac{220}{R} \]
- For the US supply (110 V):
\[ I_{US} = \frac{V_{US}}{R} = \frac{110}{R} \]
- From these equations, we can see that the current in India will be higher than in the US for the same resistance.

4. **Implications of Higher Current**:
- Higher current can lead to greater power loss in the form of heat (given by \( P = I^2 R \)).
- This means that appliances operating at higher voltages (like 220 V) can be designed to draw less current for the same power output, which can be more efficient.

5. **Safety Considerations**:
- Lower voltage (110 V) is generally considered safer for human contact, as it reduces the risk of severe electric shock.
- Higher voltage (220 V) can be more dangerous but is more efficient for power transmission over long distances.

6. **Cost Implications**:
- Appliances designed for lower voltage (110 V) may require thicker wires or more robust components to handle higher currents, making them more expensive to manufacture and maintain.
- Conversely, appliances designed for higher voltage (220 V) can be less expensive to maintain due to lower current requirements.

7. **Conclusion**:
- The correct statement is that 110 V is safer but more expensive to maintain due to the need for thicker wiring and components to handle the higher current.

### Final Answer:
The correct statement is: **110 V is safer but more expensive to maintain.**