ancillae. 1  nominative plural of. 2  genitive singular of. 3  dative singular of.  vocative plural of.
Acceleration is the time rate of change of velocity. If velocity is constant, then. acceleration is zero. Note: 100 km per h for 10 seconds is a constant speed, but not necessarily a constant. velocity, since we're told nothing about the direction.
Acceleration is any change in the velocity vector. You know what acceleration is because you've been in a vehicle that speeds up, slows down or takes a sharp corner. When the car speeds up (accelerates) it pushes against your back as it accelerates you.