The depth of the troughs of a wave is called its

Options

A. amplitude
B. displacement
C. frequency
D. none of these

Answer

**Step-by-Step Solution:**

1. **Understanding Wave Structure**: A wave consists of alternating high points called crests and low points called troughs. The trough is the lowest point of the wave.

2. **Identifying the Depth of the Trough**: The depth of the trough refers to how far the trough is from the normal (equilibrium) position of the wave. This depth is measured vertically from the normal line to the bottom of the trough.

3. **Defining Amplitude**: The amplitude of a wave is defined as the maximum displacement of points on a wave from the rest position (normal line). This means that the amplitude can be measured from the normal line to either the crest or the trough.

4. **Relating Trough Depth to Amplitude**: Since the depth of the trough is a measure of how far the wave dips below the normal line, it is equal to the amplitude of the wave. Therefore, the depth of the trough can be referred to as the amplitude of the wave.

5. **Evaluating Other Options**:
- Displacement refers to the shortest distance between the starting and ending points of the wave's motion and is not related to the depth of the trough.
- Frequency is the number of cycles per second and does not relate to the depth of the trough either.
- Therefore, the only correct term for the depth of the trough is amplitude.

6. **Conclusion**: The depth of the trough of a wave is called its amplitude.

**Final Answer**: The depth of the trough of a wave is called its **amplitude**.

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