Amplitude of vibrations can change in

Options

A. a progressive wave
B. A transverse wave
C. in a stationary wave
D. a longitudinal wave

Answer

To answer the question "Amplitude of vibrations can change in," we will analyze different types of waves: progressive waves, stationary waves, and longitudinal waves.

### Step-by-Step Solution:

1. **Understanding Progressive Waves**:
- Progressive waves are waves that move through a medium. The particles of the medium oscillate in the direction of the wave's propagation.
- In progressive waves, the amplitude of vibrations can change as the wave travels through the medium. This means that the energy of the wave can vary, leading to changes in amplitude.

2. **Understanding Stationary Waves**:
- Stationary waves, also known as standing waves, are formed when two waves of the same frequency and amplitude traveling in opposite directions interfere with each other.
- In stationary waves, certain points called nodes do not oscillate (zero amplitude), while other points called antinodes oscillate with maximum amplitude. However, the amplitude of vibrations at any given point in a stationary wave does not change over time. Thus, the amplitude remains constant.

3. **Understanding Longitudinal Waves**:
- Longitudinal waves are waves where the oscillation of the medium is parallel to the direction of wave propagation. An example is a sound wave or a wave in a slinky.
- In longitudinal waves, similar to progressive waves, the amplitude of vibrations can change. For instance, when a slinky is compressed and released, the amplitude of the compressions and rarefactions can vary as the wave travels.

4. **Conclusion**:
- In summary, the amplitude of vibrations can change in progressive waves and longitudinal waves. However, in stationary waves, the amplitude does not change.

### Final Answer:
The amplitude of vibrations can change in progressive waves and longitudinal waves, but it does not change in stationary waves.

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