*Question E9C04:
What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?*  

*Correct Answer is  B: Additional lobes form with major lobes increasingly aligned with the axis of the antenna*  

### AI Response: (may contain errors)  

As the length of an unterminated long wire antenna is increased, the radiation pattern changes in a specific way:

1. **Correct Answer (B):** Additional lobes form with major lobes increasingly aligned with the axis of the antenna.  
   - **Explanation:** A long wire antenna, when extended, starts to exhibit multiple lobes in its radiation pattern. These lobes become more numerous and tend to align more closely with the axis of the wire. This is due to the constructive and destructive interference of the waves along the length of the wire, which creates multiple points of maximum radiation (lobes) along the wire's axis.

2. **Why Other Choices Are Incorrect:**
   - **Choice A:** Fewer lobes form with the major lobes increasing closer to broadside to the wire.  
     - This is incorrect because increasing the length of the wire actually results in more lobes, not fewer. The major lobes do not move closer to broadside; instead, they align more with the wire's axis.
   
   - **Choice C:** The elevation angle increases, and the front-to-rear ratio decreases.  
     - This is incorrect because the elevation angle does not necessarily increase with wire length. The front-to-rear ratio is more affected by the alignment of the lobes rather than just the length of the wire.
   
   - **Choice D:** The elevation angle increases, while the front-to-rear ratio is unaffected.  
     - This is incorrect because, similar to Choice C, the elevation angle is not the primary factor affected by increasing wire length. The front-to-rear ratio is influenced by the formation of additional lobes.

**Useful Rule of Thumb:**
- As the length of a long wire antenna increases, the number of lobes increases, and these lobes tend to align more with the wire's axis. This is a key characteristic of long wire antennas and is important for understanding their directional properties.