Final answer:
The question involves understanding the practical installation angle for a ground rod used in a lightning rod system. While the provided information emphasizes the importance of lightning rods being pointed to effectively bleed away electric charge, it does not directly answer the physical angle when encountering a rock. The principles of electromagnetism imply that the rod should remain as vertical as possible for optimal performance.
Step-by-step explanation:
The subject of the question relates to the optimal angle for driving a ground rod, typically used for lightning rod systems, into the ground when it encounters a rock. Given that lightning rods work best when most pointed, the largest angle in question would pertain to the physical installation rather than electrical efficiency. The text provided discusses the effectiveness of lightning rods in bleeding away induced charge to prevent lightning strikes, implicating principles of electromagnetism at play.
When installing a lightning rod or a ground rod, encountering a rock can pose a considerable challenge. The angle of the rod must be adjusted to navigate around the obstruction without compromising its vertical orientation significantly, as this could affect its operation. If a ground rod hits a rock, the common practice is to try to drive the rod at a slight angle to either side of the obstruction while striving to keep it as vertical as possible. The maximum angle is not specified in physics terms, as that would depend on various practical considerations, but the efficiency of the ground rod relies on it being close to vertical.
The question seems to involve concepts explained in illustrations about the physics of lightning rods and the forces exerted on structures like telephone poles, hence the answer leans towards foundational knowledge in physics related to lightning rod functionality and electromagnetism.