<em>The displacement of an object during a specific unit of time: </em>Velocity (the direction is part of displacement.)
<em>How fast or slow an object is moving and in what direction: </em>Velocity (speed & direction)
<em>How fast or slow an object is moving: </em>Speed (no direction)
<em>A cheetah running 97 km/h: </em>Speed (no direction)
<em>A train traveling 45 m/s north: </em>Velocity (speed & direction)
Answer:
there is no drag in a vacuum (why is father in a vaccum)
Explanation:
there is nothing to hit and slow the object other than gravity like dust or air
Answer:
Estimation: year 1110.
Explanation:
We need to know how much time it takes to move 100 arcseconds if it moves at 0.11 arcsecond per year. Similarly to any velocity equation 
, where in our case the distances are angular, we will obtain the time by doing:
Which, considering from 2019, the explosion ought to have been observed around 1110 (in reality it was observed by Chinese astronomers in 1054).
