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Mission KC4 Acceleration

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 The Question

A car with a rightward velocity and a leftward acceleration is ____.

 Physics Rules

Direction of Acceleration:
Acceleration is a vector quantity and it has a direction. For an object moving in a straight line, the direction of the acceleration is dependent upon two factors:
 
  • the direction that the object moves, and
  • whether the object is speeding up or slowing down
 
If an object is speeding up, then the direction of the acceleration is in the same direction that the object is moving. If an object is slowing down, then the direction of its acceleration is in the opposite direction that the object is moving.

 Think About It

The direction of an object's velocity is always in the same direction that the object is moving. In this question, the direction of the acceleration is in the opposite direction as the direction that the object is moving. Thus, the question concerns an object that is moving in one direction and has an acceleration in the opposite direction. Using the principle in the Know the Law section should allow you to answer this question.

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