Answer:
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Step-by-step explanation:
Whenever a force is applied in an object in the opposite direction of its motion. It tends to slow down the speed of the object. Therefore, this force is called the decelerating force and the acceleration produced by it is called deceleration.
The deceleration produced in this case by this decelerating force has a direction opposite to the direction of motion or velocity of the object. Therefore, this deceleration is defined with a negative sign along with its magnitude.
Due to this opposite direction, term negative acceleration is also used instead of deceleration.