Let's say that, for the purpose of a thought experiment, I want to use the following as a calculation of the speed of light. Assume the following scene is an inertial, non-accelerated frame. 1. I have two clocks, A and B, which start out one millimeter from each other, and are perfectly synchronized. 2. I slowly displace clock B until it is 10 km away from clock A. 3. I shine a light beam from clock A to clock B. 4. I compute time T as the difference between the time the beam was shone from clock A, to the time the beam hits clock B. 5. I compute the speed of light as (10 km) / T. Q1. Would the physics community consider the calculation in step 5 to be a legitimate calculation of the speed of light (for the purposes of a thought experiment)? Q2: Is there any inertial, non-accelerated frame of reference in which the above calculation would NOT be considered a legitimate calculation of the speed of light? I am setting the stage for future questions, but first I want to make sure I have a basic understanding of the way c can be "thought-calculated."