The transformer ratio of transformer is `10 : 1`. The current in the primary circuit if the secondary current required is `100 A` assuming the transformer be ideal, is

Options

A. `500 A`
B. `200 A`
C. `1000 A`
D. `2000 A`

Explanation

To solve the problem, we will use the relationship between the primary and secondary currents in a transformer, which is given by the formula:

\[ \frac{I_p}{I_s} = \frac{N_p}{N_s} \]

Where:
- \( I_p \) = Primary current
- \( I_s \) = Secondary current
- \( N_p \) = Number of turns in the primary coil
- \( N_s \) = Number of turns in the secondary coil

Given that the transformer ratio is \( 10:1 \), we can express this as:

\[ \frac{N_p}{N_s} = 10 \]

This implies that:

\[ N_p = 10 \cdot N_s \]

From the transformer relationship, we can rearrange the formula to find the primary current:

\[ I_p = I_s \cdot \frac{N_p}{N_s} \]

Substituting the transformer ratio into the equation:

\[ I_p = I_s \cdot 10 \]

Now, we are given that the secondary current \( I_s \) is \( 100 A \). Substituting this value into the equation:

\[ I_p = 100 A \cdot 10 \]

Calculating this gives:

\[ I_p = 1000 A \]

Thus, the current in the primary circuit is \( 1000 A \).

### Final Answer:
The current in the primary circuit is \( 1000 A \).

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