Gravitational Force elevator questions

AI Thread Summary
The discussion centers on a physics problem involving a student on a scale in an elevator, analyzing the scale readings during different elevator movements. Initially, the scale reads 836 N at rest, then increases to 935 N while ascending before returning to 836 N, indicating acceleration. As the elevator approaches the 74th floor, the reading drops to 782 N, prompting further calculations of acceleration. Participants clarify that the scale readings represent the force exerted by the elevator on the student, emphasizing the importance of understanding the forces at play. The conversation highlights the need for accurate diagrams and conceptual clarity in solving such physics problems.
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A student stands on a bathroom scale in an elevator at rest on the 64th floor of a building. The scale reads 836 N.
a) As the elevator moves up, the scale reading increases to 935 N, then decreases back to 836 N. Find the acceleration of the elevator.
b) As the elevator approaches the 74th floor, the scale reading drops as low as 782 N. What is the acceleration of the elevator?

Fnet = ma
F-mg = ma

This is all I've got so far...I'm thinking I need to find the force exerted by the elevator on the student. How?

Thanks.
 
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Oh wow...thanks!
 
The scale readings are the Force exerted by the elevator on the student.
Did you draw a sketch of this?
The only thing touching the student is the scale!
 
I drew a diagram, but somehow mistakenly thought that it is the scale exerting the force, and the elevator played no part in it. I get it now! Thanks very much for your help, lightgrav!
 

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