Elizabeth I dies and James VI of Scotland accedes to the English throne. Elizabeth I died childless so was succeeded by her cousin, James VI of Scotland, who henceforth assumed the title of James I of England as well.
T minus zero means out of time.. This comes from a countdown convention used in by both the American military and NASA. Generally, it is used when counting down to a major event that will happen at a specific time. Mathematically, T is time, minus whatever amount of time is left until the event happens.
The acceleration of a body at any instant of time such that the time t reaches to zero... a=dv/dt(t nearly reaches to zero. dv=change in velocity. dt=small change in time.