Is the Velocity of an Upward-Moving, Slowing Rock Still Positive?

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When a rock is thrown upward, its position is positive as it moves above the ground, which is defined as the origin. The velocity remains positive because the rock is still moving upward, despite slowing down. The discussion highlights the importance of defining the positive direction in physics problems, as it can lead to confusion. Participants agree that while the rock's velocity is positive, the problem should clarify the positive direction. Overall, understanding the distinction between positive velocity and the rate of change is crucial in this context.
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You throw a rock upward. The rock is moving upward, but it is slowing down. If we define the ground as the origin, the position of the rock is___ and the velocity of the rock is___.

I said that they are both positive because the rock is going up, and even though it is slowing down, it is still going up so the velocity is positive. Is my reasoning correct?
 
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I think it's looking for either an "increasing" or "decreasing" (not a "positive" or "negative")
 
Nathanael said:
I think it's looking for either an "increasing" or "decreasing" (not a "positive" or "negative")

The options show positive and negative.

I think it does make sense though, because the ball is in a positive direction relative to the ground, and the velocity is upwards, but I'm not completely sure.
 
They said the ground was the origin, but they didn't say which direction (up or down) was positive.

Your answers and reasoning are correct, but the problem really should have stated which direction is the positive direction.
 
Ah I see. Thanks!
 

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