Question

a man standing on the ground sees two lightning flashes simultaneously, 1 kilometer to the east and 1 kilometer to the west of where he is standing. since he sees the light simultaneously, and it travels equal distances, he concludes that the lightning hits the ground at exactly the same time in the two locations. what happens according to a man driving by, east to west, very close to the speed of light?
a. according to the driver, the flashes occur and are seen simultaneously.
b. according to the driver, the flashes occur simultaneously, but are seen at two different times. the east flash is seen first, and the west flash is seen last.
c. according to the driver, the flashes occur simultaneously, but are seen at two different times. the west flash is seen first and the east flash is seen last.
d. according to the driver, the flashes occur at different times and the west flash occurs last.
e. according to the driver, the flashes occur at different times and the west flash occurs first.

Explanation:

Step1: Recall relativity of simultaneity

In special - relativity, events that are simultaneous in one inertial frame may not be simultaneous in another. The ground - based observer sees the lightning flashes as simultaneous. The driver is moving from east to west.

Step2: Analyze light travel time for the driver

Since the driver is moving towards the west - flash location, the light from the west - flash has to travel a shorter distance (in the driver's frame of reference) to reach the driver compared to the light from the east - flash. So, the driver will see the west - flash first.

Answer:

C. According to the driver, the flashes occur at different times. The west flash is seen first and the east flash is seen last.