1. The problem statement, all variables and given/known data 1) Two spaceships are at rest with a distance x between them and tied together with a string. An observer standing in between the two spaceship sends them both a signal. As soon as the signal reaches each spaceship (same time in the observer frame) both spaceships start accelerating at a constant and equal acceleration. Will the string tear? 2)Now the two spaceships are flying at v with respect to the observer. They are again at a distance x apart in the observer's fram and tied together with a string. The observer sends a signal in such a way that the signal reaches the spaceships at the same time in the observer's fram. As soon as each spaceship recieves a signal they again start accelerating at a constant and equal acceleration. Will the string tear apart? 2. Relevant equations Note: my professor claims he does not know the exact answer. 3. The attempt at a solution It seems like the answer to A) is no because the string will shrink but so will the distance between the two spaceships. I'm completely lost as it comes to B. I assume the string does break just based on a purpose for the questions. Thank you so much!