Question

If the captain of ship A fires a missile, counts 10.0 s on his watch, and then fires a second missile, how much time Δt will the captain of ship B measure to have passed between the firing of the two missiles?

Answer 1

If none of the ships are moving, the elapsed time for ship B will be the same Δt = 10s

Step-by-step explanation:

If no ship is moving then the elapsed time between missiles for both ships will be the same.

On the other hand, if one of them (or both) were moving, then the relative motion of the ships would make Δt seem smaller if the ships were getting closer, or greater if they were distancing from each other.