In a transformer 220 ac voltage is increased to 2200 volts. If the number of turns in the secondary are 2000, then the number of turns in the primary will be

Options

A. 200
B. 100
C. 50
D. 20

Explanation

To solve the problem, we will use the relationship between the voltages and the number of turns in a transformer, which is given by the formula:

\[ \frac{V_s}{V_p} = \frac{N_s}{N_p} \]

Where:
- \( V_s \) = Secondary voltage
- \( V_p \) = Primary voltage
- \( N_s \) = Number of turns in the secondary
- \( N_p \) = Number of turns in the primary

### Step-by-Step Solution:

1. **Identify the given values:**
- Primary voltage (\( V_p \)) = 220 V
- Secondary voltage (\( V_s \)) = 2200 V
- Number of turns in the secondary (\( N_s \)) = 2000 turns

2. **Write the transformer equation:**
\[ \frac{V_s}{V_p} = \frac{N_s}{N_p} \]

3. **Rearrange the equation to solve for \( N_p \):**
\[ N_p = \frac{V_p}{V_s} \times N_s \]

4. **Substitute the known values into the equation:**
\[ N_p = \frac{220 \, \text{V}}{2200 \, \text{V}} \times 2000 \, \text{turns} \]

5. **Calculate the ratio of the voltages:**
\[ \frac{220}{2200} = \frac{1}{10} \]

6. **Now calculate \( N_p \):**
\[ N_p = \frac{1}{10} \times 2000 = 200 \, \text{turns} \]

7. **Final Answer:**
The number of turns in the primary (\( N_p \)) is 200 turns.