Final answer:
The question involves calculating the time difference between two simultaneous lightning strikes seen by observers at different distances. While the speed of light is considered, without an observer's relative speed, it's not possible to determine time differences without additional data.
Step-by-step explanation:
The question involves calculating the time difference between two lightning bolts seen by two observers positioned at different points with respect to the lightning strikes. Since the speed of light is extremely fast (3 × 108 meters per second), we can assume that the light from lightning reaches both the main observer and the assistant at almost the same time.
We are given that the main observer at x = 8.0 km sees both lightning strikes at the same time, with the first strike at x = 0 km and the second at x = 15.0 km. The assistant is at x = 3.0 km, closer to the first strike. The fact that light reaches both observers at the same time and the known distances makes it possible to calculate the time difference using the concepts of light travel time.
However, to answer the student's question regarding the time difference between the two lightning bolts, we would need additional information, such as the relative speed of observer to the lightning strikes — which is not provided in the question. In special relativity, the perception of simultaneity can vary based on the observer's frame of reference. With the given data, we can only state that, from the stationary observer's perspective, the two lightning bolts appear simultaneous.