Which of the following part in AC Generator is mechanically rotated in the uniform magnetic field by some external means?

Options

A. Rotor
B. Armature
C. Shaft
D. None of these

Explanation

To solve the question "Which of the following part in AC Generator is mechanically rotated in the uniform magnetic field by some external means?", we can follow these steps:

### Step 1: Understand the Components of an AC Generator
An AC generator consists of several key components, including the rotor, armature, shaft, and magnetic field. The rotor is the rotating part, while the armature is the component that generates electricity.

### Step 2: Identify the Function of Each Component
- **Rotor**: This is the rotating part of the generator, but it is not specifically the part that generates the AC.
- **Armature**: This is the part of the generator that rotates within the magnetic field and induces an electromotive force (EMF).
- **Shaft**: This is the part that connects the rotor to the external mechanical source, but it does not generate electricity itself.
- **None of these**: This option implies that none of the listed components are correct.

### Step 3: Determine the Correct Answer
Among the options provided, the armature is the component that is mechanically rotated in the uniform magnetic field to generate alternating current. The armature is specifically designed to cut through magnetic lines of force, inducing an EMF.

### Conclusion
The correct answer to the question is **Armature**.

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