Why are velocity and acceleration called vector quantities?

Acceleration is a vector quantity because it has both magnitude and direction. When an object has a positive acceleration, the acceleration occurs in the same direction as the movement of the object.a change in the direction of motion results in an acceleration even if the moving object neither sped up nor slowed down. That's because acceleration depends on the change in velocity and velocity is a vector quantity — one with both magnitude and direction.Velocity as a Vector Quantity Because the person always returns to the original position, the motion would never result in a change in position. Since velocity is defined as the rate at which the position changes, this motion results in zero velocity.

Explanation:

if a star is moving toward earth, its light waves appear to be squeezed together. hope it

i don't know that i agree with that but what's the question ?