GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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constant
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decreasing
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increasing
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neither increasing nor decreasing
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Detailed explanation-1: -This represents an object that has a constant speed. It is not speeding up or slowing down, so it has zero acceleration. Because the velocity/speed of this object is decreasing over time, this means there is a negative acceleration.
Detailed explanation-2: -Explanation: If an object is moving with constant velocity, then its acceleration must be zero.
Detailed explanation-3: -People think, “If the acceleration is negative, then the object is slowing down, and if the acceleration is positive, then the object is speeding up, right?” Wrong. An object with negative acceleration could be speeding up, and an object with positive acceleration could be slowing down.
Detailed explanation-4: -According to our principle, when an object is slowing down, the acceleration is in the opposite direction as the velocity. Thus, this object has a negative acceleration.