*Question G5B05:
How many watts are consumed when a current of 7.0 milliamperes flows through a 1,250-ohm resistance?*  

*Correct Answer is  A: Approximately 61 milliwatts*  

### AI Response: (may contain errors)  

To find the power consumed when a current flows through a resistance, we can use the formula:

$$
P = I^2 R
$$

where:
- $P$ = power in watts
- $I$ = current in amperes
- $R$ = resistance in ohms

### Step-by-step Calculation:

1. **Convert current from milliamperes to amperes**:
   - Given current $I = 7.0$ milliamperes = $7.0 \times 10^{-3}$ amperes.

2. **Use the resistance value**:
   - Given resistance $R = 1,250$ ohms.

3. **Substitute values into the formula**:
   - Calculate power:
   $$
   P = (7.0 \times 10^{-3})^2 \times 1,250
   $$
   - First, calculate $(7.0 \times 10^{-3})^2$:
   $$
   (7.0 \times 10^{-3})^2 = 49 \times 10^{-6} = 0.000049
   $$
   - Now, multiply by the resistance:
   $$
   P = 0.000049 \times 1,250 = 0.06125 \text{ watts} \approx 61 \text{ milliwatts}
   $$

### Conclusion:
- The correct answer is **approximately 61 milliwatts** (Choice A).

### Why Other Choices Are Incorrect:
- **Choice B (Approximately 61 watts)**: This is incorrect because the calculated power is in milliwatts, not watts. 61 watts would imply a much higher current or lower resistance.
- **Choice C (Approximately 11 milliwatts)**: This is incorrect as the calculation shows the power is significantly higher than 11 milliwatts.
- **Choice D (Approximately 11 watts)**: This is also incorrect for the same reason as Choice B; the calculated power is much lower than 11 watts.

### Useful Formulas:
- Power can also be calculated using Ohm's Law:
$$
P = V \times I
$$
where $V$ is voltage. However, in this case, using $P = I^2 R$ is more straightforward since we have both current and resistance. 

This explanation should help you understand how to approach similar problems on the Extra Class exam!