A wave going a solild

Options

A. must be longitudinal
B. may be longitudinal
C. must be transverse
D. may be transverse.

Answer

To solve the question regarding the nature of waves propagating through a solid, we need to analyze the types of mechanical waves and their behavior in different media.

### Step-by-Step Solution:

1. **Understand the Types of Mechanical Waves**:
- Mechanical waves require a medium to travel through. There are two main types: transverse waves and longitudinal waves.
- In transverse waves, the particles of the medium move perpendicular to the direction of wave propagation.
- In longitudinal waves, the particles move parallel to the direction of wave propagation.

2. **Identify the Propagation of Waves in Solids**:
- Both transverse and longitudinal waves can propagate through solids. This is a key point because it indicates that solids can support both types of mechanical waves.

3. **Evaluate the Options**:
- **Option 1: Must be longitudinal** - This is incorrect because waves in solids can also be transverse.
- **Option 2: May be longitudinal** - This is correct because longitudinal waves can propagate through solids.
- **Option 3: Must be transverse** - This is incorrect because waves in solids can also be longitudinal.
- **Option 4: May be transverse** - This is correct because transverse waves can also propagate through solids.

4. **Conclusion**:
- The correct options are 2 and 4. Options 1 and 3 are incorrect.

### Final Answer:
- The correct options are: **Option 2 (may be longitudinal)** and **Option 4 (may be transverse)**.