How many 60 W bulbs may be safely run on 220 v using a 5 A fuse?

Options

A. 18
B. 16
C. 14
D. 12

Answer

To solve the problem of how many 60 W bulbs can be safely run on a 220 V supply using a 5 A fuse, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Power Rating**: Each bulb has a power rating of 60 W.

2. **Determine the Total Power Capacity**: The total power that can be safely used with a 5 A fuse at 220 V can be calculated using the formula:
\[ P = V \times I \]
where \( P \) is the power in watts, \( V \) is the voltage in volts, and \( I \) is the current in amperes.

3. **Calculate the Total Power**:
\[ P = 220 \, \text{V} \times 5 \, \text{A} = 1100 \, \text{W} \]

4. **Set Up the Equation for Bulbs**: Let \( n \) be the number of bulbs. The total power consumed by \( n \) bulbs is:
\[ P_{\text{total}} = n \times 60 \, \text{W} \]

5. **Equate the Total Power to the Power Capacity**:
\[ n \times 60 = 1100 \]

6. **Solve for \( n \)**:
\[ n = \frac{1100}{60} \approx 18.33 \]

7. **Determine the Maximum Integer Value for \( n \)**: Since \( n \) must be an integer (you can't have a fraction of a bulb), we take the largest integer less than or equal to 18.33, which is 18.

### Final Answer:
Thus, the maximum number of 60 W bulbs that can be safely run on a 220 V supply using a 5 A fuse is **18 bulbs**.