Speed is a SCALAR quantity and velocity is a VECTOR quantity.
VECTOR quantities have size and direction.
The two objects on the right have the same MAGNITUDE, but different VELOCITIES because they’re going in different directions.
This is shown by the MINUS sign.
Acceleration is a change in speed, so it is a SCALAR quantity.
Acceleration in the same direction as an object moving in that direction will make that object SPEED UP.
Acceleration in the opposite direction will make an object SLOW DOWN or DECELERATE.
An acceleration of ZERO will not change the velocity of an object.
Hope that helps. :)
