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Question
A force F1 acts on a particle accelerating it from rest to a velocity v. Force F1 is then replaced by F2 which decelerates the particle to rest.
Options
F1 must be equal to F2.
F1 may be equal to F2.
F1 must be unequal to F2
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Solution
F1 may be equal to F2.
Any force applied in the direction opposite the motion of the particle decelerates it to rest.
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