When a body moves to and fro, or up and down, about a fixed position, it is said to be in _________ motion

Options

A. Oscillatory
B. Vibratory
C. rotatory
D. circular

Answer

**Step-by-Step Solution:**

1. **Understanding the Motion**: The question describes a body that moves to and fro or up and down about a fixed position. This indicates a repetitive movement around a central point.

2. **Identifying the Type of Motion**: The options given are oscillatory, vibratory, rotatory, and circular. We need to determine which of these best fits the description.

3. **Analyzing the Options**:
- **Oscillatory Motion**: This type of motion occurs when an object moves back and forth around a fixed point. A common example is a pendulum swinging.
- **Vibratory Motion**: This is similar to oscillatory motion but typically refers to smaller, rapid movements, like a tuning fork vibrating.
- **Rotatory Motion**: This involves an object rotating around an axis, like a spinning top.
- **Circular Motion**: This refers to an object moving in a circular path, such as a car turning around a circular track.

4. **Choosing the Correct Answer**: Since the question specifies movement to and fro or up and down about a fixed position, the most appropriate term is **oscillatory motion**.

5. **Final Answer**: Therefore, when a body moves to and fro, or up and down, about a fixed position, it is said to be in **oscillatory motion**.

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