ok, I think I have it, but let me try here...
If I have an engine that has a force of 1500N (150kg), and a Space vessel with a mass of 250 Tonnes (250,000kg), traveling for 48 hrs. (172,800 seconds). Then it would look like this;
a = F / m
a = 1500 / 250,000
a = 0.006
v = u + at
v =...