When three identical bulbs are connected in series. The consumed power is 10W. If they are now connected in pa rallel then the consumed power will be:-

Options

A. 30W
B. 29W
C. 10/3W
D. 270W

Explanation

To solve the problem, we need to determine the power consumed by three identical bulbs when they are connected in parallel after knowing the power consumed when they are connected in series.

### Step-by-Step Solution:

1. **Understanding the Series Connection:**
- When the three identical bulbs are connected in series, the total resistance \( R_{\text{total}} \) is the sum of the individual resistances. If each bulb has a resistance \( R \), then:
\[ R_{\text{total}} = R + R + R = 3R \]
- The power consumed in the series connection is given as \( P = 10 \, \text{W} \).

2. **Using the Power Formula:**
- The power consumed in a circuit can be calculated using the formula:
\[ P = \frac{V^2}{R_{\text{total}}} \]
- Substituting the total resistance for the series connection:
\[ 10 = \frac{V^2}{3R} \]
- Rearranging this gives us:
\[ V^2 = 30R \quad \text{(1)} \]

3. **Understanding the Parallel Connection:**
- When the bulbs are connected in parallel, the total resistance \( R' \) is given by:
\[ \frac{1}{R'} = \frac{1}{R} + \frac{1}{R} + \frac{1}{R} = \frac{3}{R} \implies R' = \frac{R}{3} \]

4. **Calculating Power in Parallel Connection:**
- The power consumed in the parallel connection can be calculated using the same power formula:
\[ P' = \frac{V^2}{R'} \]
- Substituting \( R' \):
\[ P' = \frac{V^2}{\frac{R}{3}} = 3 \cdot \frac{V^2}{R} \]
- From equation (1), we know that \( \frac{V^2}{R} = 30 \):
\[ P' = 3 \cdot 30 = 90 \, \text{W} \]

5. **Conclusion:**
- The power consumed when the three identical bulbs are connected in parallel is \( 90 \, \text{W} \).

### Final Answer:
The consumed power when the bulbs are connected in parallel is **90 W**.