@ould the elevator be moving up or down?

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The discussion centers on a physics problem involving a student in an elevator. The student, weighing 615 N, observes a scale reading of 645 N, indicating an apparent increase in weight. This suggests that the elevator is accelerating upwards, as the scale measures the normal force exerted on the student. A counterargument points out that if the elevator were accelerating downwards, the scale reading would decrease. Therefore, the conclusion is that the elevator is indeed moving up.
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elevator ??

A 615 N student standing on a scale in an elevator notices that the scale reads 645 N. would the elevator be moving up or down?
 
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What do you think is the answer (and why)?
 
well i think that he would be moving down because the scale says he got heavier. i think that the force pushing down would make him seem heavier
 
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Not so. The elevator must either be accelerating up or down for his scale to show a different reading. The reading is nothing but the force the scale exerts on the person to keep him in place with respect to the elevator. Let's assume that the elevator is accelaratig down, then you can easily show from a free body diagram that the scale reading must decrease. Therefore he is accelerating up.
 

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