When are stationary waves produced?

Answer

**Step-by-Step Text Solution:**

1. **Understanding Stationary Waves**: Stationary waves, also known as standing waves, are formed when two waves of the same frequency and wavelength travel in opposite directions and interfere with each other.

2. **Characteristics of Stationary Waves**: In stationary waves, certain points called nodes remain stationary (do not move), while other points called antinodes oscillate with maximum amplitude.

3. **Condition for Formation**: For stationary waves to be produced, two waves must meet the following conditions:
- They must have the same frequency.
- They must have the same wavelength.
- They must travel in opposite directions.

4. **Superposition Principle**: When these two waves meet, they superimpose on each other. This superposition leads to the formation of stationary waves, where the energy is not transferred along the medium, but rather the energy oscillates between the nodes and antinodes.

5. **Visual Representation**: If we visualize the stationary wave, we can see that the nodes are points of no displacement, while the antinodes are points of maximum displacement. This can be depicted graphically, showing the reference line and the oscillating wave pattern.

6. **Conclusion**: Therefore, stationary waves are produced when two waves of the same frequency and wavelength travel in opposite directions and superimpose on each other.

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