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Is the distance an object moving increases with time if it is accelerated with a constant rate?

I mean, doesn't it depend on the direction the object is traveling? if I throw an object upward, wouldn't the distance it travels per second decrease due to the deceleration of gravity?

This was the question, it was from my final PHYS101 exam:

If an object is undergoing constant acceleration, the distance it travels per second is:

A. Increasing with time
B. Decreasing with time
C. Constant with time
D. Depends on the direction it travels

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  • $\begingroup$ @John Having answer D as a possibility implies we should not assume an initial zero velocity. $\endgroup$
    – PM 2Ring
    May 13 '18 at 23:12
  • $\begingroup$ I edited the post to write the exact question (I forget adding something). I don't know if it would make a difference. $\endgroup$ May 14 '18 at 9:24
  • $\begingroup$ I would choose D, but as a physicist I would say is badly worded. It would be better if it said "Depends on the direction it travels relative to the acceleration" $\endgroup$ Feb 22 '20 at 23:11
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There is definitely ambiguity with your exam. Acceleration can refer to deceleration, but sometimes people consider these two to be separate.

After re-reading the exact question asked, whether or not it is accelerating or decelerating is irrelevant. Even if it is decelerating, the object will still be moving forward and hence the distance should be increase.

The ambiguity here is, distance with respect to what?

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  • $\begingroup$ That's why I chose D $\endgroup$ May 13 '18 at 19:55
  • $\begingroup$ @GhassanSaeed What's the problem? $\endgroup$ May 13 '18 at 19:57
  • $\begingroup$ I believe the right answer is A, as most of my friends said, but Im not convinced. $\endgroup$ May 13 '18 at 19:59
  • $\begingroup$ @GhassanSaeed Without thinking of edge cases, I'm not surprised people would say it's A. I'd recommend asking for a regrade request from the professor. $\endgroup$ May 13 '18 at 20:01
  • $\begingroup$ I edited the post to write the exact question (I forget adding something). I don't know if it would make a difference. $\endgroup$ May 14 '18 at 9:24
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The question doesn't give us enough data for an answer but I will point out 3 cases:

1) For an object without any velocity, the correct answer is (a). The direction of acceleration is not important since it is moving away from a point, so the total space covered by the object would be the same.

2) For an object with constant velocity, if the direction of the velocity is the same with the direction of the acceleration, then the correct answer is (a), since the object will gain velocity.

3) For an object with constant velocity, if the direction of the velocity is opposite to the direction of the acceleration, then the correct answer is (b), since the object will lose velocity.

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