*Question G9B04:
What is the radiation pattern of a dipole antenna in free space in a plane containing the conductor?*  

*Correct Answer is  A: It is a figure-eight at right angles to the antenna*  

### AI Response: (may contain errors)  

The correct answer to the question about the radiation pattern of a dipole antenna in free space is:

**A: It is a figure-eight at right angles to the antenna.**

### Explanation of the Correct Answer:
- A dipole antenna radiates electromagnetic waves in a pattern that is strongest in the plane perpendicular to the antenna. This results in a figure-eight pattern when viewed from above.
- The radiation is minimal along the axis of the antenna (the ends), and maximum at right angles to it, creating the characteristic lobes of the figure-eight.

### Why the Other Choices are Incorrect:
- **B: It is a figure-eight off both ends of the antenna.**
  - This is incorrect because the radiation pattern is not strongest at the ends of the dipole; instead, it is weakest there. The lobes are oriented perpendicular to the antenna, not off the ends.

- **C: It is a circle (equal radiation in all directions).**
  - This choice describes an isotropic radiator, which is a theoretical antenna that radiates equally in all directions. A dipole does not have this characteristic; it has a directional pattern.

- **D: It has a pair of lobes on one side of the antenna and a single lobe on the other side.**
  - This is incorrect because the dipole's radiation pattern is symmetrical. It has two equal lobes on either side of the antenna, not an unequal distribution.

### Useful Rules of Thumb:
- The radiation pattern of a dipole antenna can be visualized as a "doughnut" shape, with the antenna running through the center.
- The maximum radiation occurs in the plane perpendicular to the antenna, while the minimum occurs along the axis of the antenna.

Understanding these concepts will help you visualize and remember the radiation patterns associated with dipole antennas for your Extra Class exam.