When the plane of the armature of an ac. generator is parallel to the field , in which it is rotating

Options

A. both the flux linked and induced emf in the coil area zero
B. the flux linked with it is zero, while induced emf is maximum
C. flux linked is maximum while induced emf is zero
D. both the flux and emf have their respective maximum values.

Answer

To solve the question regarding the condition of the armature of an AC generator when it is parallel to the magnetic field, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Setup**:
- The armature of the AC generator is rotating in a magnetic field. When the plane of the armature is parallel to the magnetic field lines, we need to analyze the relationship between the magnetic flux and the induced EMF.

2. **Identifying the Angle**:
- When the plane of the armature is parallel to the magnetic field, the area vector (A) of the armature is perpendicular to the magnetic field (B). This means that the angle (θ) between the area vector and the magnetic field is 90 degrees.

3. **Calculating Magnetic Flux**:
- The magnetic flux (Φ) linked with the armature can be calculated using the formula:
\[ \Phi = A \cdot B \cdot \cos(\theta) \]
- Substituting θ = 90 degrees:
\[ \Phi = A \cdot B \cdot \cos(90^\circ) = A \cdot B \cdot 0 = 0 \]
- Therefore, the magnetic flux linked with the armature is zero.

4. **Induced EMF Calculation**:
- The induced EMF (ε) in the generator can be expressed as:
\[ \epsilon = \epsilon_0 \cdot \sin(\theta) \]
- When the armature is parallel to the magnetic field, the angle θ between the direction of motion and the magnetic field is 90 degrees (the angle for maximum EMF):
\[ \epsilon = \epsilon_0 \cdot \sin(90^\circ) = \epsilon_0 \cdot 1 = \epsilon_0 \]
- This indicates that the induced EMF is at its maximum value.

5. **Conclusion**:
- In summary, when the plane of the armature is parallel to the magnetic field, the magnetic flux linked with it is zero, while the induced EMF is at its maximum.

### Final Answer:
- The correct conclusion is that when the plane of the armature of an AC generator is parallel to the magnetic field, the magnetic flux linked is zero, and the induced EMF is maximum.