In transformer , power of secondary coil is :

Options

A. less than primary coil
B. more than primary coil
C. more in step up less in step down than primary coil
D. None of these

Answer

To solve the question regarding the power of the secondary coil in a transformer, we will follow these steps:

### Step-by-Step Solution:

1. **Understanding the Transformer**:
A transformer consists of two coils, the primary coil and the secondary coil, wound around a magnetic core. The primary coil receives input power, while the secondary coil delivers output power.

**Hint**: Remember that a transformer operates on the principle of electromagnetic induction.

2. **Power in an Ideal Transformer**:
In an ideal transformer, the power input to the primary coil is equal to the power output from the secondary coil. This can be expressed mathematically as:
\[ P_{\text{input}} = P_{\text{output}} \]
where \( P = V \times I \) (Power = Voltage × Current).

**Hint**: The concept of power conservation is crucial in understanding how transformers work.

3. **Power Calculation**:
If we denote the voltage and current in the primary coil as \( V_p \) and \( I_p \), and in the secondary coil as \( V_s \) and \( I_s \), we can write:
\[ V_p \times I_p = V_s \times I_s \]
This means that if the voltage increases in the secondary coil, the current must decrease, and vice versa.

**Hint**: Consider how the turns ratio affects voltage and current in the transformer.

4. **Types of Transformers**:
- In a **step-up transformer**, the voltage in the secondary coil is greater than in the primary coil (\( V_s > V_p \)), which results in a lower current in the secondary coil (\( I_s < I_p \)).
- In a **step-down transformer**, the voltage in the secondary coil is less than in the primary coil (\( V_s < V_p \)), which results in a higher current in the secondary coil (\( I_s > I_p \)).

**Hint**: Identify whether the transformer is a step-up or step-down to understand how voltage and current relate.

5. **Conclusion**:
Regardless of whether the transformer is a step-up or step-down type, the power remains constant in an ideal transformer. Therefore, the power of the secondary coil is equal to the power of the primary coil.

**Final Answer**: The power of the secondary coil is equal to the power of the primary coil in an ideal transformer.

**Hint**: Always assume ideal conditions unless specified otherwise in problems involving transformers.