GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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An object has velocity directed east and acceleration directed west.
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An object has velocity directed east and acceleration directed east.
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An object has zero velocity but non-zero acceleration.
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An object has constant non-zero acceleration and changing velocity.
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Detailed explanation-1: -C) an object has constant nonzero velocity and changing acceleration Not possible: velocity cannot be constant in the presence of a non-zero acceleration.
Detailed explanation-2: -Let’s take an example of a particle moving in a uniform circular motion, it has acceleration because the direction of the motion is changing but it has a constant speed along tangential throughout the motion. Yes, it is possible to have constant acceleration and varying speed.
Detailed explanation-3: -Yes, you can have a zero velocity and a nonzero acceleration. Think of a case where the acceleration vector is pointing in the opposite direction of your velocity vector. The acceleration causes the velocity to keep on decreasing, until such point that the object’s instantaneous velocity goes to zero.
Detailed explanation-4: -Solution : A body may have zero velocity but non-zero acceleration. For example, when a body is thrown vertically upwards at the maximum height the body momentarily comes to rest.
Detailed explanation-5: -the direction changes. Acceleration is the rate of change of velocity. As the velocity is changing, an acceleration is produced. Therefore, in uniform circular motion an object moves with an acceleration but with uniform speed.