Fill in the following blanks with suitable words :
One of the most well known periodic motion is that of a ...............

Answer

**Step-by-Step Solution:**

1. **Understanding Periodic Motion**: First, we need to define what periodic motion is. Periodic motion is a type of motion that repeats itself at regular intervals of time.

2. **Identifying Examples**: Next, we think of common examples of periodic motion. The most familiar examples include the motion of a pendulum, the motion of a swing, or the rotation of a wheel.

3. **Choosing the Best Example**: Among these examples, the simple pendulum is often cited as one of the best-known examples of periodic motion because it clearly demonstrates the concept of repeating motion over time.

4. **Filling in the Blank**: Based on our understanding and examples, we can fill in the blank in the sentence provided. The completed sentence would be: "One of the most well known periodic motion is that of a **simple pendulum**."

**Final Answer**: One of the most well known periodic motion is that of a **simple pendulum**.

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